46MnVS series steel for cracking connecting rod and manufacturing method of 46MnVS series steel

Abstract

The steel comprises the following chemical components in percentage by mass: 0.44 to 0.48 percent of C, 0.60 to 0.75 percent of Si, 1.10 to 1.20 percent of Mn, 0.015 to 0.045 percent of P, 0.06 to 0.070 percent of S, 0.20 to 0.28 percent of Cr, 0.10 to 0.18 percent of Ni, 0.08 to 0.15 percent of Cu, less than or equal to 0.03 percent of Mo, less than or equal to 0.008 percent of Al, 0.020 to 0.040 percent of Nb, 0.13 to 0.18 percent of V, 0.015 to 0.021 percent of N, 0.01 to 0.02 percent of Ti and the balance of Fe and inevitable impurity elements. The structure of the connecting rod is ferrite and pearlite, the content of the ferrite is 5%-15%, and the grain difference of the large-head expansion section of the connecting rod is 0.5-1 level. The yield strength Rel of the connecting rod is greater than or equal to 800MPa; and the rejection rate in the expansion breaking process is less than or equal to 0.1%.

Description

technical field [0001] The invention belongs to the technical field of iron-based alloys, and in particular relates to a manufacturing method of 46MnVS series steel for expanding connecting rods. Background technique [0002] The 46MnVS5 steel for expanding connecting rod was imported from Germany. The advantages of the material are high strength and long fatigue life. With the development of automobiles in the direction of energy saving and light weight, it is used to replace the C70S6 series expanding connecting rod. [0003] 46MnVS5 steel was introduced into China, and each main engine factory revised the grades and standard requirements, such as 46MnVS6, 46MnVS5mod, 46MnVS6mod, etc. This application is collectively referred to as 46MnVS series steel. [0004] The steel is smelted according to the chemical composition in foreign technical specifications, and the connecting rod is made by domestic customers, and the structure of the connecting rod is often abnormal. The f...

AI Technical Summary

Problems solved by technology

[0004] The steel is smelted according to the chemical composition in foreign technical specifications, and the connecting rods are made by domestic customers. There are often abnormalities in the structure of the connecting rods. Before processing the connecting rods, a small batch of tests is required, and the adjustment of the connecting rods during the processing of the connecting rods is based on the test results. The forging and cooling process is used to meet the comprehensive performance required by the connecting rod. This production method is not conducive to mass production; at the same time, due to process adjustment and the same equipment as C70S6 series steel is still used for production, the connecting rod produced by 46MnVS5 during the expansion process The scrap rate is too high, and the scrap rate has reached 2% to 10%, causing serious waste

Images