2019-10-15 15:26:28

Technological Analysis of Low Alloy Wear-Resistant Steel for Bucket Tooth of Excavator

According to the application contrast test of bucket teeth steel of excavator, in order to achieve the ideal comprehensive performance, the quenching heating temperature adopted is different from that of conventional hypoeutectoid steel: Ac3+ (3O-50). Rather, higher temperature is chosen.

For example, ZG30CrMnsffee steel and ZG27CrZSIMnMOVA steel, the critical points of Ac3 are 85O C and 840 C, respectively. According to the conventional setting, the quenching temperature of bucket teeth of excavator is up to 900 C, but the quenching result is not ideal. The strength of steel decreases slightly when the quenching temperature is raised to 1050 C.

The reason for choosing higher quenching temperature is believed to be beneficial to homogenization of composition, further reduction of high carbon micro-zone, increase the number of high dislocation lath martensite and thin film retained austenite, so as to improve the self-strengthening and toughness of steel, enhance the ability to resist crack propagation, reduce stress concentration and improve toughness.

 

The quenching methods of bucket teeth low alloy wear resistant steel of excavator are mainly direct quenching or isothermal bainite treatment to obtain lath martensite and thin film retained austenite or lath martensite plus lower bainite with good combination of strength and toughness. Tempering after quenching is also very important. According to the traditional concept, the plasticity and toughness of steel are improved by increasing tempering temperature, but the situation of low alloy wear-resistant steel is different. Increasing tempering temperature not only decreases the hardness value of wear resistance, but also decreases the plasticity and toughness to varying degrees, which is extremely harmful to the performance of bucket teeth of excavators.

 

The test results show that tempering at 150 - 200 C is suitable for bucket teeth of excavator.

 

Huangzuan Machinery established in 2008, is a specialized manufacturer of bucket teeth, bucket adaptor and side cutter which is used Caterpillar, Komatsu, Hyundai, Daewoo, Kobelco, Hensley, Liugong, Hitachi, XCMG, XGMA, Volvo, Esco, JCB .etc.