M4 is a high speed tool steel specifically designed for better wear resistance than M2 or M3.
Specifications:
UNS T11304, ASTM A600, SAE J437, SAE J438, QQ-T-590, CPM M4,
Applications:
Punches, die inserts, cutting tools
Data is typical and should not be construed as actual values for any catagory. Applications and technical information require engineers and tool designers to exercise independent judgement