Lead-free Copper Alloy Research Articles

A New Lead-Free Copper Alloy CuAl8Fe5Ni4Zn4Sn1 for Plain Bearings and Its Strengthening Mechanisms

CuAl8Fe5Ni4Zn4Sn1 (OF 2238) is a new lead-free copper alloy for plain-bearing applications that was first officially presented in a scientific journal in 2020. Soon after its invention, the use of the alloy for connecting rod bushings in heavy-duty internal combustion engines was promoted and validated with customers. The aim of this article is to describe the material properties of the new alloy in more detail than previously and explain how the advantageous properties of CuAl8Fe5Ni4Zn4Sn1 are generated. At the beginning of this article, the general development trends in the field of copper alloys for sliding applications are presented, into which the new alloy from this publication can be classified. In the main part of this publication, the authors go through the production chain of CuAl8Fe5Ni4Zn4Sn and show how the entire manufacturing process contributes to obtaining a material with a combination of high strength, ductility and sufficient toughness. This starts with fine microstructures after casting, followed by homogenisation and refinement during hot extrusion and work hardening chiefly during cold drawing. What is most surprising, however, is the finding that a strong hardening effect can be achieved in the new alloy by precipitation of fine κ-phase at temperatures of about 400 °C and air cooling without prior solution treatment. These results make it clear that there is great potential for further material developments to support material efficiency and even to expand the application limits.

Study on damage evaluation of bimetal with the lead-free copper alloy (Life evaluation in bending fatigue test with AE method)

Study on damage evaluation of bimetal with the lead-free copper alloy (Life evaluation in bending fatigue test with AE method)

Effect of Annealing on Micro Drilling of Lead–Free Copper Alloy C6932

Effect of Annealing on Micro Drilling of Lead–Free Copper Alloy C6932

Corrosion Behavior of Lead-Free Copper Alloy Castings and Their Crystallized Substances of Cu<sub>2</sub>S and Bi

Corrosion Behavior of Lead-Free Copper Alloy Castings and Their Crystallized Substances of Cu<sub>2</sub>S and Bi

Development Of Lead Free Copper Alloy Casting; Mechanical Properties, Castability and Machinability

The regulation for the lead discharge in the environment was strengthened, in Japan, the standards 0.01 mg/I or less has been in force from April 2003. In order to meet the new standard, two technologies for reduction of lead dissolution into the drinking water have been developed in Japan; substitution of lead free copper alloys for lead bearing bronze (JIS-CAC406) and introduction of surface treatment technology. This technological trend was shortly reviewed. For development of lead free copper alloy casting, mechanical properties, castability and machinability of various lead free alloy castings were examined. Trial alloys used were commercially available ones such as the lead free bronze containing Bi, the lead free bronze containing Bi-Se, the lead free bronze containing Bi-Sb and the lead free brass containing Si. Mechanical properties of alloys were dependent on the pouring temperature and castings thickness and were generally less than those of tin bronze castings (JIS-CAC406, Cu-5 wt% Sn-5 wt% Zn-5 wt% Pb). The machinability of the lead free bronze containing Bi and Se was better than that of the lead free bronze castings containing Bi and Bi-Sb. But was still 10 to 15 % less than that of JIS-CAC406. In a lead free alloy substituted by Bi, adjustment of tin, zinc and bismuth contents was attempted and in the Bi-Se system, the adequate adjustment, for bismuth and selenium contents and also for tin, zinc and bismuth contents, was attempted. New alloy in which the mechanical properties sufficiently satisfy the standard for JIS-CAC406 is developed.

Study on material properties’ evaluation of lead free copper alloy by AE method

Study on material properties’ evaluation of lead free copper alloy by AE method

鉛フリー銅合金を用いたバイメタル材の摩擦・摩耗特性の評価に関する研究

鉛フリー銅合金を用いたバイメタル材の摩擦・摩耗特性の評価に関する研究

Corrosion Behavior of Lead-Free Copper Alloy Castings and Their Crystallized Substances of Cu<sub>2</sub>S and Bi

Corrosion Behavior of Lead-Free Copper Alloy Castings and Their Crystallized Substances of Cu<sub>2</sub>S and Bi

Tribology of Lead-Free Copper Alloy Castings

Tribology of Lead-Free Copper Alloy Castings

AE法による鉛フリー銅合金を用いたバイメタル材の損傷評価に関する研究

The lead bronze is widely used as the sliding materials. However, the development of lead free copper alloy has been advanced, because the use restriction of lead is carried out. In this study, the application of AE method was examined for evaluating the characteristics of the bimetal materials of lead free copper alloy which changed the distribution of the hydrosulphide in which the slide characteristics are improved by the addition of sulfur. As the results, it was possible to show the possibility for evaluating the damage conditions by using the frequency analysis, m value and Ib value of the AE signals detected in tensile and fatigue test.

Effect of Surface Texturing Arrangement for Improving Anti-Seizure Property of Lead-Free Copper Alloy

Lead-bronze is widely used in the automotive industry owing to its excellent anti-seizure property. However, lead is toxic, and thus, from an environmental viewpoint, there is a demand for a lead-free copper alloy in the automotive industry. Despite the anti-seizure property of lead-free copper alloy being comparable to that of lead-bronze, it has not yet been well exploited. Therefore, the objective of this study was to improve the anti-seizure property of lead-free copper alloy using a laser surface texturing (LST) method. A ring-on-ring sliding friction tester was used to assess the effectiveness of LST and to investigate the effect of surface texturing arrangement on the anti-seizure property of lead-free copper alloy. In the friction tests, upper specimens made of FCD700 and lower specimens made of PBC2 (lead-free copper alloy) were used. Paraffinic oil was used as a lubricant and was circulated using a pump. Results of the friction tests showed that the textured specimens demonstrated superior anti-seizure property to that of the non-textured specimens. Further, on the basis of the obtained experimental results, it was concluded that the arrangement of dimples plays an important role in improving the anti-seizure property of lead-free alloy.

20415 ディンプルテクスチャの配置が銅合金の耐焼付き性向上に与える影響

It is well known that lead-bronze is widely used in the industry owing to the high anti-seizure property. However, because of toxicity of lead, the industry demands a lead-free copper alloy from the viewpoint of environment. For this reason, the objective of this study is to improve the anti-seizure property of lead-free copper alloy using a laser surface texturing (LST). In this study, a ring-on-ring sliding friction tester was used to investigate the effect of surface texturing arrangement on the anti-seizure property of lead-free copper alloy. The upper specimens were made of FCD700, while the textured bottom specimens were made of PBC2 (lead-free copper alloy). A hydraulic fluid oil was used as a lubricant and it could be circulation. The friction test results showed that the arrangement of dimples plays an important role in improving the anti-seizure property.

Study on damage evaluation of bimetal with lead-free copper alloy (Application of Acoustic Emission method)

Study on damage evaluation of bimetal with lead-free copper alloy (Application of Acoustic Emission method)

Effectiveness of Surface Texturing for Improving the Anti-seizure Property of Copper Alloy

It is well known that lead-bronze is widely used in the automotive industry owing to the high anti-seizure property. However, because of toxicity of lead, the automotive industry demands a lead-free copper alloy from the viewpoint of environment. Lead- free copper alloy, which has the anti-seizure property as high as lead-bronze, has not been yet well exploited. For this reason, the objective of this study is to improve the anti-seizure property of lead-free copper alloy using a laser surface texturing (LST). In this study, a ring-on-ring sliding friction tester was used to assess the effectiveness of LST on the anti-seizure property of lead- free copper alloy. The upper specimens were made of FCD700, while the textured bottom specimens were made of PBC2 (lead- free copper alloy). A Daphne Hydraulic Fluid 32 (Idemitsu) paraffinic oil was used as a lubricant. The sliding friction test was conducted with a running-in period for 10min at a load of 50N. Afterwards, the load was increased incrementally from 50N to 1600N, while the friction coefficient was measured simultaneously. The friction test results showed that the textured specimens have a better anti-seizure property compared to the non-textured specimens. Based on the obtained experimental results, it was concluded that the arrangement and area ratio of dimples play an important role in improving the anti-seizure property.

Casting Structure and Mechanical Properties of Lead-free Bronze Castings Containing Bismuth as Alloying Element

Bismuth-bearing bronze alloy is drawing attention as a lead-free copper alloy substitute for CAC406 alloy. Effects of the bismuth content and cooling rate on the casting structure and mechanical properties of bronze alloys were investigated. The decrease in the liquidus line reduced with increasing bismuth content, resulting in a large change in the alloying components such as zinc and bismuth. The bismuth content of 3 mass% is appropriate for controlling composition and obtaining a good castability under the same casting conditions as CAC406 alloy. Small pores are formed in the bismuth-bearing bronze alloy. The amount of pores was found to increase with increasing bismuth content. In addition, higher cooling rates of the alloy during casting diminished the amount of pores and increased bulk density. Uniform dispersion of fine bismuth particles (about 10 μm) and grain refinement led to higher strength and higher elongation of the alloy. A 3 mass% bismuth-bearing bronze alloy of 2 mm in thickness showed more than 50% elongation and 300 MPa tensile strength.

Production Technology and Application of Bismuth-Selenium Lead Free Copper Alloy Castings

Production Technology and Application of Bismuth-Selenium Lead Free Copper Alloy Castings

Lead Free Copper Alloy Casting

Lead Free Copper Alloy Casting

Effect of Notch on Tensile and Fatigue Strengths of Lead Free Copper Alloy Castings

Effect of Notch on Tensile and Fatigue Strengths of Lead Free Copper Alloy Castings

Properties of CAC804 Lead-Free Copper Alloy

Properties of CAC804 Lead-Free Copper Alloy

Evaluation of melt quality of lead free copper alloy castings using cooling curve

The melt quality of bronze castings such as JIS CAC406 has successfully checked by observing a fractured surface of specially designed test sample on the melting spot. Lead free copper alloy castings, however, are not successfully applied by this method because the fractured surface does not show a characteristic feature or colour. In this study, the cooling curve method cast into shell cup mould was applied to evaluate and establish melt quality. Melts, under various kind of atmosphere such as over oxidised, hydrogen absorbed, flux covered, adequately deoxidised and so on, were evaluated to check the cooling curve in a cup. Owing to the melting atmosphere, liquidus temperature and solidification behaviour showed a distinct difference. Another application of cooling curve method was carried out to deoxidising process in industrially clean melt. Phosphorus content necessary for and also during deoxidising process was well determined.