(1) Fatigue test of ordinary HT250 lifting Faraday compression
The lifting diagram of tension compression fatigue limit of ordinary HT250 is shown in Figure 1.
The tensile compressive fatigue limit of ordinary HT250 sample at 50% survival rate is:
(2) Lifting Faraday compression fatigue test of low alloy HT250
The diagram of tension compression fatigue limit rise and fall of low alloy HT250 is shown in Figure 2.
The tensile compressive fatigue limit of low alloy HT250 specimen at 50% survival rate is:
(3) Ht3000 lifting Faraday compression fatigue test results
The lifting diagram of HT300 tension compression fatigue limit is shown in Figure 3.
The tensile compressive fatigue limit of HT300 sample at 50% survival rate is:
It can be seen from Fig. 1, Fig. 2, Fig. 3 and the calculation results that the high-frequency tension compression fatigue strength of three grades of gray cast iron samples is 75.9mpa, 85.9mpa and 101.1mpa in turn. The tensile compressive fatigue strength of low alloy HT250 added with trace alloying elements is 13.1% higher than that of ordinary HT250, and that of HT300 is 17.7% higher than that of low alloy HT250.