A kind of preparation method of eccentric wheel powder metallurgy

Abstract

The invention discloses a method for manufacturing an eccentric wheel through powder metallurgy. The method comprises the following step: the eccentric wheel is manufactured by the following raw materials in percentage by weight: 0.2-0.4 percent of nickel, 0.4-0.6 percent of molybdenum, 0.6-0.8 percent of tin, 0.3-0.5 percent of aluminium oxide powder, 0.8-1 percent of graphite powder, 0.4-0.6 percent of petroleum wax, 4-6 percent of copper, 1-2 percent of performance additive and the balance of iron. According to the invention, through the added performance additive, superfine powder is provided in the mixed material, and the superfine powder can be filled in the gaps of large particles, so that apparent density of the mixture is improved; the superfine powder is mainly formed by nano-zinc oxide powder and calcium stearate, and through additives including a silane coupling agent and the like, a novel performance additive is obtained, and various physical properties about wear resistance and the like of the product are further improved, and as polyethylene vinyl acetate and liquid petrolatum are taken as lubricants to be added into the performance additive, the effect of the performance additive during mixing and pressing is enhanced, the blank pressing strength of a powder metallurgy structural piece under equal pressing pressure is greatly improved, combination form and pore shape of raw material particles are changed, and the problem about crack generation is solved from the root cause.

Description

technical field [0001] The invention mainly relates to a preparation method of eccentric wheel powder metallurgy, which belongs to the field of casting. Background technique [0002] With the continuous development of my country's economy, powder metallurgy structures are used more and more widely. As a near net shape technology, powder metallurgy has great economic advantages in the production of structural parts and other parts with large batches, high dimensional accuracy and high processing costs. However, there is a weakness in powder metallurgy structural parts: the compact strength of the product before sintering is very low, which leads to cracks easily appearing during the forming and handling process, and cannot be detected during the manufacturing process. This is a fatal defect in some applications such as key parts of automobiles, which leads to the application of powder metallurgy structural parts only to low- and medium-risk stress-bearing parts, and the scop...

AI Technical Summary

Problems solved by technology

The material composition affects the manufacturing cost, the product density has a great influence on the loss of the molding machine and the mold, and the crack is mainly affected by the strength of the compact, and it is difficult to detect