Preparation for free-cutting adnic alloy

Abstract

A free-cutting nickel-copper alloy is disclosed whose ingredients by percent are that: carbon<=0.3, manganese <=2.0, iron<=2.5, sulphur 0.025-0.060, silicon<=0.5, copper 28.0-34.0, the rests are nickel, the manufacturing method of the free-cutting nickel-copper alloy comprises the steps of: 1, loading and vacuumizing; 2, controlling the temperature within the range from 1500 to 1650 DEG C, refining for 5 to 25 minutes, adding deoxidizer and finally the sulphide to lead the sulphur content in the nickel-copper alloy to be between 0.020% and 0.08%, the optimized sulphur content is 0.040% 0.06%, the sulphide is one of manganese sulphide, iron sulphide, copper sulphide and high nickel matte or mixture thereof, the deoxidizer is one of carbon and nickel-magnesium alloy, calcium-silicon alloy, and copper-zirconium alloy or the mixture thereof; 3, measuring the temperature and casting at the temperature between 1400 and 1500 DEG C for 30 seconds at most, and vacuumizing for at least 10 minutes; the good cutting performance of the steel remarkably improves the cutability of steel, reduces the cutting force and cutting temperature, conspicuously prolonging the life of cutting tool, lessens the surface roughness of working piece and improves the cut-processing performance.

Description

technical field [0001] The invention relates to a preparation process of a free-cutting nickel-copper alloy material, and in particular provides a preparation method of a free-cutting nickel-copper alloy. Background technique [0002] According to the different free-cutting elements, it can be divided into sulfur free-cutting steel, lead free-cutting steel, calcium free-cutting steel, titanium free-cutting steel and composite free-cutting steel. The most widely used is sulfur free cutting steel. It is generally believed that as the sulfur content increases, the machinability of steel is better, but for ordinary steel, a slight increase in sulfur can significantly improve the machinability; adding appropriate sulfur (especially when the sulfur is lower than 0.1% or less), the effect of improving the machinability of steel is very significant. Its role is mainly manifested in: not only reducing the cutting force and cutting temperature, significantly improving tool life, but...

AI Technical Summary

Problems solved by technology

If the oxygen content in the alloy liquid is high, it is easy to form hard oxide spots, and the oxides are easy to concentrate at the tail of the ingot, so that the cutting performance of the steel is also greatly affected

The above two factors have a great influence on the uniformity of easy cutting

[0006] The content of manganese and oxygen in free-cutting nickel-copper is high, and it will have physical and chemical reactions with some components in the refractory material at high temperature, so that the refractory material will be corroded; the free-cutting nickel-copper alloy liquid has high viscosity and poor fluidity. The pouring temperature must be increased, but at the same time, free-cutting nickel-copper is a crack-sensitive steel, and a weak cooling system must be adopted. These contradictory requirements make the production process of free-cutting steel very difficult.

Images