Wear resistant cast steel for agricultural machinery subsoiler and heat treatment process thereof

Abstract

The invention discloses wear resistant cast steel for agricultural machinery subsoiler. The wear resistant cast steel comprises the following chemical components in percentage by weight: 0.29-0.34 of C, 0.40-0.50 of Si, 1.45-1.60 of Mn, 0.65-0.80 of Cr, S not more than 0.020, P not more than 0.020, and the balance of Fe and inevitable impurities. The subsoiler prepared by the wear resistant cast steel is heated by an electric furnace after casting, cleaning, polishing and machining; and the heat treatment process comprises the following steps: (1) total annealing: the temperature of the furnace is heated to reach 900-920 DEG C, and is insulated by 3 h; and the subsoiler is discharged from the furnace for air cooling after being cooled below 300 DEG C along with the furnace; (2) normalizing: the temperature of the furnace is heated to reach 880-900 DEG C, and is insulated by 2 h; and the subsoiler is discharged from the furnace for air cooling; (3) quenching: the temperature of the furnace is heated to reach 860-880 DEG C, and is insulated by 2 h; and the subsoiler is discharged from the furnace for liquid cooling; and (4) tempering: the temperature of the furnace is heated to reach 240-250 DEG C, and is insulated by 3 h; and the subsoiler is discharged from the furnace for air cooling. Through reasonable matching of the chemical components and the heat treatment process, the subsoiler is higher in hardness and tensile strength, is excellent in impact toughness, and is low in manufacturing cost.

Description

technical field [0001] The invention relates to the technical field of steel material processing, in particular to a wear-resistant cast steel for subsoiling shovels of agricultural machinery and a heat treatment process thereof. Background technique [0002] In recent years, my country has vigorously promoted the application of subsoiling technology. Subsoiling operation is an important mode of low-tillage and no-tillage farming, which can protect the soil. The core working part of this farming method is the subsoiling shovel. When the subsoiler is working, it will be subjected to severe wear and impact of different loads, and requires high wear resistance and good impact toughness. In order to reduce wear, many researchers have used special heat treatment on the surface of the subsoiler shovel, or used cladding and coating technology on the surface. These methods have improved the wear resistance of the material to a certain extent, but the use of these technologies is bou...

AI Technical Summary

Problems solved by technology

Since the matrix of the wear-resistant alloy is still martensite, the brittleness is still relatively high. In addition, the addition of high-priced ferro-boron alloy and ferro-titanium modifier will increase the material cost, and at the same time, the modification process will also increase the manufacturing difficulty.