Environment friendly free-cutting leadless copper alloy material and processing technology

Abstract

The invention relates to an environment-friendly free cutting copper alloy material. The compositions of the environment-friendly free cutting copper alloy material are 30 to 45 percent of zinc, 0.05 to 2.0 percent of aluminum, less than or equal to 1.0 percent of iron, less than or equal to 0.5 percent of boron, less than or equal to 0.5 percent of titanium, less than or equal to 0.3 percent of one element or more than one element in a rare earth element RE system, less than or equal to 0.01 percent of plumbum, less than or equal to 0.1 percent of stibium, less than or equal to 0.3 percent of unavoidable impurities and the balance being copper; and 0.05 to 1.6 percent of phosphor or 0.05 to 3.0 percent of silicon or 0.1 to 3.0 percent of magnesium or 0.05 to 3.0 percent of silicon and 0.05 to 0.5 percent of tin or 0.05 to 3.0 percent of silicon, 0.05 to 0.5 percent of tin and 0.05 to 0.5 percent of manganese are added into the compositions for mixture, and the mixture is cast into blanks after mixture. The lengthening and drawing coefficient is controlled to between 1.05 and 2.6, and the annealing temperature is controlled to between 300 and 400 DEG C. The copper alloy has the cutting performance of leaded brass, simplifies the processing technique, saves the step of intermediate annealing, and reduces the processing cost.

Description

technical field [0001] The invention belongs to the technical field of copper alloy materials, and in particular relates to an environment-friendly easy-cutting copper alloy material and a processing technology. Background technique [0002] Lead brass has excellent properties such as easy cutting, mechanics, and physics, and is a widely used copper alloy. The utilization rate of brass water pipes in developed countries is as high as 90%. [0003] Free-cutting lead brass is a two-phase brass, and lead is dispersed in the grain and grain boundary as fine particles. When copper is used as drinking water pipe fittings such as faucets and pipe joints, lead will be leached into the water under the action of substances in the water, because lead is a harmful element that can cause serious harm to the environment and human body, so its application is increasingly strict limit. [0004] In order to reduce the harmful effect of lead, researchers have systematically studied the corr...

AI Technical Summary

Problems solved by technology

In recent years, alloys have added bismuth and antimony instead of lead to form free-cutting copper alloys to achieve environmental protection and lead-free purposes. However, bismuth resources are limited and expensive. The control of antimony by NSF61 in the United States is also relatively strict, and the standard for the dissolution value of antimony is 0.6 μg / L, second only to the control of cadmium. At the same time, antimony has adverse effects on human health. It can be seen that the application of antimony has limitations, so the development of alternative environmentally friendly free-cutting lead-free copper alloys is of great significance