At the same time of crankshaft machining, we need to carry out some related tests on the crankshaft. What are the specifics?

1. Coloring penetration detection of the crankshaft
Using the method of coloring and non-destructive testing to detect the crankshaft in the process, 8 crankshafts were selected (6 of which were finished quenching, 2 were finished quenching, 6 were 40Cr, and 2 were 42CrMo). For the test, the specific test results are shown in Table 2.
(1) Through the non-destructive testing of the eight crankshafts in Table 2, it is concluded that all the quenched workpieces have cracks in the joints between the quenched and non-quenched parts, and the cracking phenomenon is more serious.
(2) The cracking phenomenon of the workpiece of 42CrMo material after quenching is slightly less than that of the workpiece of 40Cr material after quenching.
(3) It is found that there is a serious crack at the joint between the quenched portion and the non-quenched portion of the workpiece. Determine the ring-shaped hemp crack generated by the crankshaft in the heat treatment-high frequency induction hardening process.

2. Magnetic particle testing
A scrapped crankshaft was selected for destructive non-destructive testing (40Cr for quenching, and the grinding position was at the mounting of the main tile at both ends).
Destructive non-destructive testing of the crankshaft results in a crack depth of 2.2 to 2.5 mm due to quenching, and a surface hardness of 52 to 56 HRC after grinding.