Bismuth-manganese-aluminum-cerium additive for lead-free free-cutting bismuth brass, and preparation method

Abstract

The invention relates to a bismuth-manganese-aluminum-cerium additive for lead-free free-cutting bismuth brass, and a preparation method. The additive is characterized by comprising the following chemical components in percentage by weight: 13-17% of Bi, 59-63% of Mn, 13-17% of Ce, and 7-11% of Al. The preparation method of the additive comprises the following steps: weighing pure bismuth powder, manganese powder, aluminum powder and cerium powder according to proportion, adding into a small-size powder mixing machine for fully mixing, then pouring into a metal mold, pressing into rod-like materials at normal temperature through a hydraulic press, and putting into a brass pipe to produce bismuth-manganese-aluminum-cerium intermediate alloy of lead-free free-cutting bismuth brass. The adopted preparation method has the advantages of being simple in technique, and free from the burning loss of raw materials due to the use of a casting method, and being highest in bismuth yield, and free from the follow-up treatment.

Description

technical field [0001] The invention relates to a bismuth manganese aluminum cerium additive for lead-free free-cutting bismuth brass and a preparation method. Background technique [0002] Because of its good cutting performance, physical properties, mechanical properties and high cost performance, lead brass has the largest production and application of HPb59-l (equivalent to C3771). It is widely used in the production of light industry, electrical appliances, bathroom plumbing fittings, valves, etc. However, lead in brass will leach out in water, and if it enters the human body, it will seriously endanger human health. Replacing lead with non-toxic or low-toxic substances is the main way to reduce lead pollution. In order to reduce the environmental pollution caused by the disposal of lead brass in various manufacturing industries, lead-free free-cutting brass must be used. Lead-free free-cutting bismuth brass is to improve the composition of brass, and add a small amo...

AI Technical Summary

Problems solved by technology

The melting and casting method not only needs to open the furnace in advance to prepare the master alloy, but also causes the burning loss of bismuth and other alloying elements during the casting process.

The resulting bulk master alloy has a small contact area between the bulk material and the melt, and the reaction process is slow, resulting in serious burning of bismuth and other precious metals.