Mechanical performance test of engine starting motor drive gear

1. Hardness layer depth detection

The results show that the surface hardness is 56-60hrc, the core hardness is 40-42hrc, and the layer depth is 0.6-0.85mm, which meets the technical requirements.

2. Tensile and impact test

The tensile and impact specimens are made on the shaft of the gear for tensile and impact tests. According to the national standard GB / t3077, the test data are: tensile strength RM = 1165mpa (≥ 1080mpa), lower yield strength rel = 900MPa (≥ 850mpa), elongation of area a = 13% (≥ 10%), reduction of area ψ= 60% (≥ 45%), impact energy akuz = 75j (≥ 55j), the test results meet the standard requirements.