Understanding IACS: The International Annealed Copper Standard for Electrical Conductivity

The conductivity of copper catalyzes its application across many industries, including power transmission and electronics manufacturing. But how does one measure and standardize performance for such an element? Enter the International Annealed Copper Standard (IACS)—the universal grading system that assesses the degree of conductivity of copper and its copper-based alloys. In this article, we discuss the relevance of IACS, how it is created, how it is used, and its importance in quality control across the board. This overview should bring some insights into one of the most practical aspects of material engineering for professionals in the field or just a layman interested in the world behind modern-day electricals.

What is IACS, and why is it essential in the electrical industry?

IACS is the abbreviation of International Annealed Copper Standard. This was developed to determine the electrical conductivity of materials. In the electric business, it is significant because it ensures a common reference point for the effectiveness of conductive items. Most pure, experiencing IACS of 100% serves as an international benchmark; IACS refers to the amount of solvent that will dissolve the particular substance. So, pure copper is between 0 and 100 in value on the IACS index. This standard is adopted to ensure uniformity of materials selection, ensuring that engineers do not compromise the performance of the electrical systems and components. This IACS allows engineers to make evaluations and comparisons, enhancing global technologies by developing the required advanced electrical infrastructure.

Definition of IACS and its origin in 1913

The International Annealed Copper Standard (IACS) is a copper conductivity metric that can be easily understood around the globe. IACS was created in 1913 to create a reference that could be used consistently; IACS is a benchmark conductance of pure, annealed copper. Pure annealed copper was determined to be the benchmark grade because, at the time, it possessed the best conductivity among all metals, which is the reason why IACS defined that benchmark as 100% conductance.

With the onset of the 20TH century, massive electrification and industrialization fueled the need for the IACS to be set in stone as a uniform system. That’s why there was a push towards standardization of measurements, which is what IACS helped achieve. For reference, copper, which has been annealed with the above-mentioned 100% conductance, has its standard value set as 1.7241 microhms per centimeter of electrical resistivity. This standard remains constant for other materials and serves as a basis for comparison.

Aluminum and silver, for example, are rated using the IACS. Silver exhibits a slightly higher conductivity than copper, which is approximately 105% IACS, whereas aluminum is in the region of 61%. The establishment of the IACS made choosing materials for different purposes easier and provided a valuable basis for the ordered advancement of electrical technologies in subsequent decades. IACS is still relevant today, as designing and evaluating adequate electrical infrastructure globally is critical.

The significance of IACS in measuring electrical conductivity

The scope of the International Annealed Copper Standard (IACS) extends to providing a reference standard that is indispensable for measuring electrical conductivity. Setting the conductivity of pure annealed copper equal to IACS 100 allows for the relative comparison of various materials used in electrical engineering. Such a standard guarantees the right choice of materials that enable engineers to build efficient systems in terms of performance and energy usage.

How IACS relates to pure copper and other conductive materials

According to the International Annealed Copper Standard (IACS), pure, annealed copper’s electrical conductivity is 100%. In its annealed condition, pure copper possesses an electrical conductivity of about 5.8 × 10⁷ S”m^(-1) at 20°C. This value serves as a reference for measuring other conductive substances. For example, silver, the most conductively efficient metal, outrivals pure copper with an IACS number of approximately 106 under the same conditions. Conversely, aluminum, commonly employed for electrical applications due to its lightweight features, has a comparative conductivity relative to copper of about 61% IACS.

Brass or bronze have a much poorer relative conductivity on the IACS scale, usually having some conductivity between 15% and 40% IACS, depending on the specific alloy composition. Some high-performance materials, such as copper alloys, which contain additives like chromium or beryllium for strength, usually have a conductivity of 50-95% IACS. The capacity to measure and evaluate these values is essential for determining performance in specific uses, such as in the power transmission, electronics, and telecommunications industries.

Similarly, material science advancements continue to change how conductivity parameters are shaped. For example, the invention of an almost perfect copper (99.99 percent or greater purity) has made conductivity measurements approach the theoretical boundaries, which is beneficial for incorporating these technologies more precisely. Also, using the IACS scale guarantees the usefulness of these advancements since they conform to recognized conductivity standards, which enables uniformity and accuracy in designs throughout various sectors.

How is IACS used to measure the conductivity of different metals?

The standard value of 100% IACS for pure annealed copper

The standard value of 100 of the International Annealed Copper Standard (IACS) is assigned to pure copper wire because of its excellent electrical conductivity. This means that it can carry electricity quite easily. It means that a value of 1.7241 micro-ohm centimeter (µΩ cm) at 20 degrees Celsius corresponds to a resistivity of this range value. Any other metals are then compared to this standard value to measure conductivity in percentage.

The development of material sciences and high-precision manufacturing has made it possible to make copper to higher purity levels, which means minimum resistance and better performance. For instance, some widely used metals, such as aluminum, tend to have conductivities of about IACS 61 to 65 percent, while silver, which has the most conductivity, surpasses copper at approximately 105 percent IACS. These levels enable engineers to tailor materials for specific purposes, whether efficiency, weight, or low-cost effectiveness.

Comparing the conductivity of various materials using IACS

The copper standard of the International Annealed Copper Standard (IACS) at 20 degrees Celsius is pure annealed copper. This benchmark enables experts to evaluate the degree of electrical conductivity in various materials. The table below illustrates conductivity rates for the most popular materials:

• Uses of Copper: Elongated wires and copper pipes have a conductivity of 100 percent IACS. Due to copper’s ample supply and its exceptional durability, it is the material of choice in electrical wiring.
• Uses of Silver: Affected with an even higher dielectric constant than copper wire, Silver is ideal for specific applications. It is estimated that silver conductivity ranges from 102 to 105 percent IACS. Used for high-performance applications such as high-frequency connectors or circuits.
• Uses of Aluminum: Aluminum can sometimes reach as high as 105 percent IACS. Weighing considerably less than copper, aluminum is ideal for power transmission line construction. Although not as conductive as copper, it is much cheaper and easier to obtain.
• Uses of Gold: 68 to 70 percent  IACS. Most often, gold is utilized in areas that require high levels of resistance to corrosion, such as electronic connectors and aerospace parts.
• Nickel: about 22% IACS. Although it does not have the same conductivity as other metals, it is used in select applications due to its strength and corrosion resistance.
• Zinc: approximately 28%. Widespread in galvanization, zinc is used to coat surfaces rather than as a conductor.
• Iron (Steel): This ranges from 10% to IACS. Iron and steel do not rank very high in conductivity, and for that reason, they are not selected very often. They are, however, useful for structural components or in magnetic materials.

These values indicate that conductivity alone is insufficient to justify the selection of a material for electrical conduction. Application circumstances such as weight, costs, thermal properties, and corrosion resistance must be considered. Performance is further optimized for advanced alloys and composite materials, which have also been studied to solve modern engineering issues.

IACS ratings for common metals and alloys

The International Annealed Copper Standard, or IACS, is often employed as a reference for the electrical conductivity of metals and their alloys. Following are the approximate IACS ratings for some of the most popularized materials:

• Copper (annealed): 100%
• Silver: 105%
• Aluminum (pure): 61%
• Gold: 70%
• Brass: 28%
• Nickel: 22%
• Steel (carbon): 3% – 15%

Iron (pure) has notably more limited applicability as an electrical conductor than copper wire and aluminum alloys since its IACS is 17% lower than the two materials mentioned above.

These values indicate relative electrical conductivity, with annealed copper serving as the baseline standard at 100. Material selection needs to meet performance expectations, which in this case include the level of conductivity and other operating limitations.

What are the practical applications of IACS in wire manufacturing?

IACS and its influence on wire selection for electrical applications

The International Annealed Copper Standard (IACS) is vital for deciding whether a metal can be shaped into a wire for electrical systems. The factors that can aid or impede the performance, as well as the life span of the cables in certain conditions, are heavily dictated by the material’s conductivity. The factors are discussed below:

Performance Conductors

Gold is utilized for specialized applications, such as circuit boards, connectors, and other components that must withstand corrosion and reliably function while having conductivity limitations. This performance corresponds to a conductivity of 70 percent IACS.

With conductivity exceeding 100 percent, silver is invaluable in RF connectors and in many high-sensitivity systems like other high-frequency applications that demand unmatched electrical performance.

General Electrical Wiring

Due to its unrivaled conductivity, copper is the industry standard for most wiring applications and is used mainly in electrical applications worldwide. Copper is IACS-rated at 100 percent and has high thermal efficiency and mechanical durability.

Aluminum communication wires are generally favored for overhead power lines due to their 61% IACS conductivity. Being lightweight and cost-effective put them considerably ahead of their copper competition in weight-sensitive applications.

Strength and Structural Support

Brass is rated at 28 percent IACS, and while it possesses moderate conductivity, it lacks strength. This makes its use for connectors, terminals, and other components that must be strong and very effective.

Steel possesses 3 to 15 percent IACS but is usable in components like armored cabling, where structural strength and durability are essential. Although steel alloys have low conductivity, their mechanical strength outperforms the rest.

Magnetic and Inductive Applications 

Pure Iron (17% IACS): Iron is used in transformers and motors because it possesses moderate conductivity and sufficient magnetic solidness for electromagnetic applications.

Nickel (22% IACS): Resistance against oxidation renders nickel useful in environments needing endurance, such as thermocouple wires and heating elements.

Corrosion Resistance 

Stainless Steels: Stainless steels are selected for applications where resistance to environmental conditions such as moisture or salinity is critical. They have conductivity values lower than conventional copper (3%-10% IACS).

Wires are designed with specific requirements such as electrical efficiency, durability, weight, and resistance to environmental conditions in mind. With excellent knowledge of IACS values and their implications, that is possible. These performance characteristics of the materials wires make them ideal for conducting materials in wire technology.

How wire manufacturers use IACS to classify their products

Wire manufacturers use IACS to determine the grade of their wires and the material’s level of electrical conductivity. Different materials are tested compared to pure copper, with a benchmark grading of 100% IACS. Metals with a higher score than copper can contribute more to electrical conductivity. These metals are ideal for uses where high resistance to electricity needs to be applied. Alternatively, metals that do not score as high are used in scenarios where other factors like strength or resistance to corrosion need to be prioritized. This classification enables manufacturers to select the best material for every given case.

The relationship between IACS and wire gauge

Understanding the IACS relationship with wire gauge entails functionality and scaling. In my opinion, the higher the value of IACS, the better the conductivity of the material, which means the electrical current a wire made from that material can carry is more significant. The wire gauge definition refers to the size of the wire; the smaller the number, the thicker the wire. For high current applications, thicker wires are preferred; wire IACS is high to reduce resistance and energy loss in electrical conductors. On the other hand, thinner wires (higher gauge numbers) are used for applications where space and weight are constricted, but some level of size conductive efficiency is required.

How does IACS relate to thermal conductivity and other material properties?

Correlation between electrical conductivity (IACS) and thermal conductivity

As a percentage of the IACS, a given base metal’s electrical and thermal conductivity are related due to the material’s atomic structure and electron configuration. This correlation is defined by the Wiedemann-Franz Law, which asserts that thermal and electrical conductivities are proportional to absolute temperature for all metals. In other words, those metals with a degree of conductivity higher than others will be governed by the Lorenz number, which is 2.45 x 10-8 WK-2 for most metals at room temperature.

Copper, the most commonly used metal when considering conductivity, provides an example of this relationship with an electrical conductivity of 100% IACS and a thermal conductivity of approximately 400 W/m·K at 20 °C. Likewise, silver, regarded as a metal with high thermal and electrical conductivities, surpasses copper in electrical conductivity, around 105% IACS, and higher thermal conductivity of around 430 W/m·K. These parameters hold a strong relationship and are helpful in engineering so that materials with higher efficiencies of electric and thermal energy can be used.

On the other hand, materials with low electrical conductivity, such as stainless steel, ~2-3% IACS, have poor thermal conductivity and dissipation, generally lower than 20 W/m·K. For this reason, such materials can be used in areas with a high degree of mechanical or corrosive strength but are not ideal for applications that are thermally conductive or require dissipation.

Grasping these correlations is critical for selecting the best materials for heat exchangers, electrical circuits, and electronics requiring thermal and electrical management.

IACS and its impact on mechanical properties of metals

The International Annealed Copper Standard (IACS) is mostly referenced to judge the electrical conductivity of different materials, which, in the case of pure annealed copper, is set to 100%. This standard helps choose a material for an electrical application and hints at the mechanical compromises that may need to be made. Efficient materials, such as metals or alloys with high conductivity, like pure copper (100% IACS) and aluminum (60-65% IACS), tend to have poorer mechanical performance than their lower conductivity counterparts.

For example, pure copper, which has the best conductivity of all metals, has a relatively poor tensile strength of 200–250 MPa after annealing. On the other hand, some copper alloys like CuCrZr or CuBe with a considerably lower IACS rating of 60–85% have a much greater tensile strength ranging from 500–1000 MPa, depending on the composition. Hence, they are ideal for use in applications that require moderate electric conductivity but high strength, like connector terminals and high-performance wiring.

A similar phenomenon can be observed in aluminum, where there is a balance between mechanical characteristics and conductivity. With a conductivity of around 65% IACS, pure aluminum possesses a tensile strength of nearly 90 MPa, while the strengthened alloys 6061 or 7075 have a tensile strength of about 300-700 MPa. These alloys have lower conductivity, around 30-40 % IACS, but remain essential for industries that rely on lightweight and durable materials, such as aerospace and automotive manufacturing.

This balance is essential for engineering designers because the materials used must satisfy the conditions for both the electrical and mechanical performance of the parts.

What are the IACS values for common copper alloys and alternatives?

IACS ratings for brass, bronze, and beryllium copper

• Brass: Shows values of IACS between 15 – 40% conductivity depending upon the composition, with the higher zinc content demonstrating lower conductivity.
• Bronze Usually ranges from 10 – 30% IACS conductivity owing to the tin and other alloying components.
• Beryllium Copper: In its normal state, a 15 to 30 percent IACS rating is observed, but conductivity can be altered somewhat due to heat treatment and changes in composition.

Such values indicate the importance of mechanical strength and conductivity, which contradict each other.

Aluminum and its alloys: IACS values and comparisons to copper

Contrary to pure copper, which boasts a conductivity rating of 100% IACS, aluminum exhibits an impressive electrical conductivity of roughly 61% IACS. This, coupled with the fact that aluminum is significantly lighter and cheaper, clearly provides aluminum with a favorable conductivity-to-weight ratio.

Aluminum alloys tend to have a lower conductivity compared to pure aluminum due to the specific inclusions used, which are anywhere from 30 to 50% IACS. These reductions, however, are caused by alloying elements capable of enhancing mechanical properties, yet at the safe expense of conductivity. Despite this, aluminum and its important alloys tend to be utilized extensively in electricity power transmission lines, mainly due to their fraction of the weight and cost when put against pure metals.

High-conductivity copper alloys and their IACS ratings

Copper alloys with the highest level of conductivity are copper alloyed materials such as King Copper, copper wires, connectors, and integrated circuits. They all require high electrical performance. Compared with pure copper, which has an IACS of 100, other forms filed under The International Annealed Copper Standard do not perform as well.

Several alloys with high mechanical or thermal properties have higher conductivity.

Electrolytic Tough Pitch (ETP) Copper

ETP copper, or Electricore, is the standard material for most electroconductive purposes because of its 98-100 IACS conductivity, and ETP is composed of 99.90% copper with oxygen. The oxygen, in trace amounts, ensures adequate fabrication and performance.

Oxygen Free High Thermal Conductivity (OFHC) Copper 

Because of the ultra-high purity (>99.95%) along with the lack of oxygen content, Oxygen copper achieves conductivity in the range of 99-100 IACS. For best performance, OFHC is perfect for copper wire. This copper is highly valued in aerospace and semiconductor industries due to its high thermal conductivity and lack of impurities.

Silver-Bearing Copper (Cu-Ag)

By adding small quantities of silver, ranging from 0.03 to 0.1%, this alloy can reach around 95-98% IACS conductivities. Silver enhances the strength of the copper matrix, making it ideal for electric contacts or thermally challenged components like motor commutator bars.

Copper-Chromium (Cu-Cr)

Copper-chromium alloys’ strength and wear resistance make them suitable for industrial use, such as welding electrodes and high-current switches. Their conductivity is estimated to be between 80% and 90% IACS.

Beryllium Copper (Cu-Be)

Although beryllium Copper is not as conductive as pure copper, the conductivity range for Beryllium copper alloys usually lies between 20% and 60% IACS. These alloys have an exceptional balance of moderately high conductivity, hardness, and fatigue resistance, making them perfect for spring-loaded electrical connectors and other applications sensitive to tolerances.

The balance between conductivity and mechanical performance is critical when selecting an appropriate copper alloy for a particular application. However, the engineering requirements regarding electrical conductivity will always remain. Due to their advantages, the need for high-conductivity copper alloys will never vanish.

How does oxygen content affect the IACS rating of copper?

The impact of oxygen on copper’s conductivity

The quantity of oxygen contained in copper greatly influences its conductivity. High-purity copper, also known as oxygen-free copper, has a very low percentage of oxygen, thus achieving a nearly 100% IACS conductivity. On the other hand, copper with a higher rate of oxygen may create oxides that impede electron flow and result in lower conductivity. For such reasons, applications that require the utmost electrical efficiency favor oxygen-free copper.

IACS values for oxygen-free copper vs. standard copper

Oxygenated free copper possesses an IACS (International Annealed Copper Standard) conductivity value of 99% to 100%, making it suitable for top-notch electrical and electronic applications. This fantastic conductivity is attainable because the material is highly pure, generally containing 0.001% oxygen or less. OFC (Oxygen-Free Copper) and OFHC (Oxygen-Free High Conductivity) are known as oxygen-free copper types. They are prevalent in telecommunications, aerospace, and power industries because of their enhanced efficiency and reliability.

Oxygenated Free Copper yields better performance than electrolytic tough pitch (ETP) copper, which contains oxygen in a value of 0.01-0.04%. Standard copper exhibits lower conductivity in the 97% to 99% IACS region. The ETP copper’s oxygen content is beneficial because it enables a completely controlled manner, allowing for the controlled creation of copper oxides, which restrict electron flow and slightly decrease electrical performance. However, ETP copper proves efficient for typical electrical applications regardless of its comparably low-performance metrics.

Now that such a comparison has been performed, the significance of strategically picking such a type of copper based on specific requirements such as conductivity, costs, and environmental conditions is amplified.

What factors can influence the IACS rating of a material?

The effect of alloying elements on IACS values

The International Annealed Copper Standard (IACS) rating of any material depends on the type and volume of alloying ingredients used. Alloying ingredients are added to base metals like copper to change their mechanical, thermal, or electrical characteristics. These changes also decrease the material’s electrical conductivity compared to pure copper because they hinder the unimpeded movement of electrons.

For instance, minute quantities of silver (Ag) or magnesium (Mg) will improve strength and only slightly degrade conductivity. Strength and conductivity are significant features of copper. When copper is alloyed with silver, it doesn’t drop below 95% of IACS and prevents thermal softening. On the other hand, phosphorus (P) is added to improve the strength and machinability of phosphor bronzes. Still, the conductivity usually drops between 15% to 40% IACS, depending on the amount of phosphorus used.

Aluminum (Al) is another alloying ingredient in copper-aluminum alloys. Aluminum considerably lowers conductivity by 40% to 60% IACS. This conductivity reduction is acceptable in structural applications like the marine environment, where strength and corrosion resistance are sought more than electrical performance.

Nickel (Ni), as a component of copper-nickel alloys, is known to lower conductivity to roughly 5% to 50% IACS, depending on the amount of nickel used. However, these alloys are favored because of their enhanced ability to resist biofouling and corrosion from salt water, particularly in the marine and offshore industries.

Accurately measuring these effects is central to selecting a material because even insignificant changes in the composition of the alloy can cause drastic changes in conductivity. Material specifications often cover such changes since such alloys negatively affect the performance of the mechanisms for which they were designed and constructed. Still, electrical and mechanical standards must also be fulfilled.

How temperature and processing affect IACS ratings

IACS ratings vary extensively because of the temperature and processing of a material, as they are known for changing electron mobility and microstructure. Higher temperatures are generally known to increase vibrations within the lattice, which, in turn, impedes the flow of electrons. This, therefore, reduces the overall conductivity of a material. IACS ratings, on the other hand, increase due to the reduction of internal stresses caused by processing techniques such as annealing, which aid in aligning grain structures, thus improving electron movement. Cold working can reduce conductivity due to the destruction of the ordered arrangement of a material’s atoms and the introduction of dislocations. This is more common with metals. These factors must be adequately controlled during manufacturing to achieve the correct conductivity and mechanical strength required.

The role of impurities in determining IACS conductivity

The conductivity of a material is fundamentally dependent on its impurities, which interrupt electron flow and subsequently determine its IACS. Selective elements can drastically alter the electric conductivity of materials. In copper, receiving any phosphorus or tin, and even arsenic as an impurity, is damaging due to its ability to act as an electron scattering center and reduce overall conductivity. The conductivity of high-purity copper, 99.99% in composition, is rated close to 100%. However, copper with 0.03% of any impurity component reduces conductivity by 10 %.

The scattering of conduction electrons results from erratic disruptions within the crystal lattice; such interactions of electrons with the atoms of impurities are the reason behind the reduced conductivity. The presence of certain elements, like oxygen, in the form of secondary phases or highly soluble elements makes these effects worse due to their change in the microstructure of the matrix. The conductivity of copper is poor because the inclusion of cupric oxide (COO) results in an incredible amount of nonconductive substances.

Recent developments in material engineering are on removing impurities using methods like electrolytic refining and zone melting to increase electric conductivity. Compounds formed are analyzed by ICP-MS (Inductively Coupled Plasma Mass Spectrometry) for precise quantification of impurities versus numeric standards. For more demanding uses like electromagnetics and power grids, the impurity threshold is usually kept under 0.01% for the required standards of IACS to be met.

Frequently Asked Questions (FAQs)

Q: What does IACS stand for, and what is its relevance to electrical conductivity?

A: The IACS measures conductivity and represents the International Annealed Copper Standard. The IEC established it, and it is used to benchmark the conductivity of other materials against that of pure annealed copper, which is 100% IACS.

Q: Which aluminum alloys have IACS values closer to copper and correspondingly higher conductivity?

A: Many aluminum alloys have less conductivity compared to pure copper. Take, for example, the 6061-T6 aluminum alloy, whose conductivity is approximately 43 percent IACS compared to 100% IACS of pure copper wire. Notwithstanding, the weight and cost efficiency of aluminum makes it a popular choice in electrical applications.

Q: Which factors may influence the conductivity properties of materials?

A: Several factors affect the electric conductivity of materials, including temperature, purity, alloying elements, and heat treatment. For example, increasing temperature generally increases resistivity, while increasing purity and proper heat treatment can enhance conductivity.

Q: How is IACS applied to determine the high purity conductivity of copper, say above 99.9%?

A: IACS serves as a standard reference for the austenitic electrical conductivity of copper with high purity. For pure annealed copper, the standard of 100 IACS is used for copper at 20°C. Any sample of copper that exceeds this point of reference is said to have an IACS value of more than 100, which means that copper has extremely high conductivity.

Q: Why is IACS 101% important in aspects of copper conductivity?

A: A conductivity of 101 IACS of copper is beneficial because it shows an advancement of the material with electrical conductivity compared to the reference standard of annealed pure copper. This is possible by adopting sophisticated refining methods followed by perfect control of the copper’s impurities so that the end product is copper of outstanding purity and high conductivity.

Q: In what ways does IACS support material selection for electrical connectors and conductors?

A: IACS assists in determining the most appropriate materials for electrical connectors and conductors by providing an everyday basis for evaluating the electric conductivity of various materials. The lower the resistivity of a material, the greater the IACS value; thus, the material is more competent for electrical applications.

Q: Are there materials possessing interceding conductivity between copper and aluminum?

A: Conductivity measures a material’s ability to let electricity pass through it. There are materials possessing interceding conductivity between copper (100% IACS) and aluminum (approximately 61% IACS). For instance, some copper alloys having small proportions of other elements, such as zinc or nickel, can have conductivities in this range. These materials have a good balance of strength, resistance to corrosion, and conductivity.

Q: How does IACS assist the United States Department of Commerce in Electrical Standards?

A: The United States Department of Commerce has accepted IACS to measure electrical conductivity. This standardization of the electrical measurements and specifications jointly used by various industries and applications makes it easier to trade and standardize electrical components.

Q: Is using IACS to assess the conductivity of materials other than metals feasible?

A: Normally, a unit of conductivity is allocated mainly for metals like copper wires or aluminum alloys, but it can also be used for comparing other materials, albeit less frequently. In the case of non-metals with extremely low conductivity, such a comparison is of no practical value, and other techniques and measurement units are used predominantly.

Q: What is the correlation between tensile strength and conductivity in IACS units?

A: In metals, there is usually a relationship of inverse proportion between the tensile strength and the conductivity. With work hardening or alloying, the material’s tensile strength tends to increase. Conductivity depreciates, so copper is made to be fully annealed. Hence, IACS values jump to 100, and copper alloys, on the other hand, albeit having lower IACS values, tend to have significantly higher tensile strength and a lot more stress resistance.

Reference Sources

1. The conceptualization and analysis of the performance of the hybrid copper tungsten composites incorporating the tungsten Networks strengthen metals.

• Authors: Fuxing Yao et al.
• Published: 2024-01-26
• Key Findings: The authors seek to follow and evaluate this paper’s copper tungsten electrical and mechanical comportment. Among the composites, Cu-30W conducted at 44.7% IACS and Cu-10W at 80.3% IACS. This paper elaborates on how the tungsten structure is critical in reinforcing the properties of the copper matrix composites, particularly in high-temperature applications.
• Methodology: The authors evaluated the mechanical and electrical properties of the created composites by employing selective laser melting and infiltration in their synthesis.

2. Metal Molding of Pure Copper with Electron Beam – Ensuring optimal conductivity using process effectiveness monitoring techniques

•  Authors: Robert Ortmann et al.
•  Published: 2024
•  Key Findings: The research work made a great effort to fabricate copper particles with conductivity more significant than 102% IACS using the powder bed fusion forging technique. This highlights a dramatic improvement in the use of metal additive manufacturing to create high electrical conductivity copper parts.
• Methodology: To enable highly conductive samples, the authors thoroughly controlled the electron beam melting process and the quality of 3D-printed models in progress, monitoring them through video streaming.

3. Simple construction of copper/graphene materials with layered structures with superior electrical and mechanical properties.

• Authors: Wenhui Li et al.
• Published: 2024-04-03
• Key Findings: The Graphene/Copper composites offered in this study display an electrical conductivity of 105.12% IACS and a tensile strength higher than pure copper by 17%. The investigation focuses on graphene’s capability to improve copper composite properties.
• Methodology: The authors spray copper foils with graphene powder and then consolidate the resulting mixture into a composite.

4. Laserpulverbettschmelzen von reinem kupfer mit ring beam strahlen. 

• By: Bauch et al.
• Issued on: 23 Sep 2024
• Insights: It examines the use of ring-shaped beam profiles in laser powder bed fusion of copper, which achieves more than 99.5 percent density and electrical conductivity up to 101.62 percent IACS. This method appears to enhance the quality of additively manufactured copper parts effectively.
• Study design: The authors investigated the characteristics of welds produced in an experiment by evaluating the welding process and weld geometry.

5.  Leading Copper CNC Machining Service Provider  in China