Unleaded brass alloy

Abstract

The invention provides unleaded brass alloy. The unleaded brass alloy contains 59.0%-65.0% wt% of Cu, 0.1%-1.0% wt% of Si, and the balance Zn and unavoidable impurities, and the Zn equivalent X of the unleaded brass alloy is within the range of 38%-43.5%. The following formula X=(Znwt%+10.0xSiwt%+2.0xSnwt%+6.0xAlwt%) / (Cuwt%+Znwt%+10.0xSiwt%+2.0xSnwt%+6.0xAlwt %) represents the Zn equivalent X. The unleaded brass alloy has good formability and polishing performance, and is suitable for parts, of bathroom plumbing, electric products, automobiles and the like, formed by casting and forging, in particular for water faucets and other products with complex structures.

Description

technical field [0001] The invention belongs to the technical field of alloys, in particular to a lead-free brass alloy. Background technique [0002] Traditional lead brass has been used as an important basic material in electrical, mechanical, plumbing and other fields due to its excellent cutting performance, low production cost, and good processing performance. However, because lead is extremely harmful to the human body and can damage the human bone marrow hematopoietic system and nervous system, its pollution hazard has attracted great attention. Developed economies such as the United States, the European Union, and Japan have legislated to impose strict restrictions on lead content in drinking water systems, plumbing fittings, toys, household appliances, etc., such as NSF-ANSI372, AB-1953, RoHS, etc., which are gradually banned Manufacture, sell and use products containing lead. [0003] At present, a lot of research work has been done on the lead-free brass at home...

AI Technical Summary

Problems solved by technology

[0004] Adding bismuth-silicon brass overcomes the shortcoming of poor welding performance of bismuth brass, but it is easy to produce hot and cold brittleness in the thermoforming process, and bismuth is a rare and precious metal, and the production cost is relatively high (such as Chinese patent 200610005689.2, 200310120259.1, U.S. patent US6942742B1, etc.)

Antimony-added silicon brass, because antimony itself is toxic, the antimony in the brass is very easy to dissolve during use. Its faucets, valves and other wet products have been tested by NSF. The amount of antimony element dissolved in water far exceeds the standard 0.6 μg / L, there are hidden dangers of polluting the environment and endangering human health, and cannot be applied to plumbing parts (such as Chinese patents 200410015836.5, 200710070803.4, etc.)

Zirconium-added silicon brass is rare and expensive due to the scarcity of zirconium resources, and it is extremely easy to combine with oxygen, sulfur and other oxidizing media in the alloy melting process and convert into slag and lose its effect. Poor recyclability (such as Chinese patent 200810143070)

Due to the addition of titanium in silicon brass, the polishing performance of the alloy is poor, so it is not suitable for appearance parts

The addition of phosphorus in silicon brass leads to poor forging performance of the alloy and easy overburning (such as Chinese patents 200910042723.7, 200810180201.9, etc.)

Images