The cast track shoe of tractor is the most easily worn part on tractor and bulldozer. Its working conditions are relatively poor. It often has to be in the open air and in direct contact with soil and gravel, and withstand certain stress effects such as impact, tension, extrusion and bending. For a long time, the research on improving the service life of tractor cast track shoes has been an important topic at home and abroad. The following improvements have been made in the casting performance of tractor track shoes in recent years:
- Change the structure of tractor cast track shoes and thicken the size of easily worn parts. In some special cases, sealing lubrication device is also used to improve its service performance.
- Adopt a variety of manufacturing processes. For example, cast track shoes of rolling tractor are used instead of cast track shoes, and surface alloying, insert sleeve, etc.
- Choose economical and durable new tractor cast track shoe materials and corresponding heat treatment process.
At present, the research focus on improving the service life of tractor cast track shoes is still on the selection and application of track shoe materials. The purpose of the research is to obtain a higher service life of tractor cast track shoes on the one hand, on the other hand, using high manganese steel as track material has high smelting requirements and needs to consume a large amount of high-quality ferromanganese. Under the service conditions of tractor cast track shoes, high manganese steel is not easy to obtain sufficient work hardening, so it is not an ideal material for tractor cast track shoes. It is hoped to obtain an economic and durable substitute material with a service life equivalent to that of high manganese steel.
Most of the past research work evaluated the wear resistance of tractor cast track shoes directly through field experiments. The cast track shoes and high manganese steel track shoes of various test tractors were installed on the same vehicle for test comparison. This direct loading test is affected by many factors such as test conditions, production characteristics of each plant, measurement and statistical errors. The test cycle is long, the test parameters are difficult to control, and the results are scattered, so it is difficult to draw a more accurate conclusion. Therefore, it is necessary to adopt the corresponding laboratory wear test to make up for the deficiency of field test. At the same time, in order to reasonably select wear-resistant materials, we must essentially understand the damage characteristics of tractor cast track shoes and guide the selection direction and way of wear-resistant materials. Since, China has focused on the indoor wear test of tractor cast track materials, the micro analysis of wear surface and damage mechanism of tractor cast track shoes. The cast track shoes of the tractor tested are from the main manufacturers of tractors and track shoes in China, and the selected materials are representative.