HSS M42 flat bar

M42 super high speed steel is a premium cobalt high speed steel with a chemical composition designed for high hardness and superior hot hardness. These properties make the steel an excellent choice for machining high-strength and pre-hardened steels, high-hardness alloys, and the difficult-to-machine, nonferrous super alloys used in the aerospace, oil, and power generation industries.

M42 exhibits excellent wear resistance by virtue of high heat-treated hardness (68 to 70 HRC), and the high cobalt content imparts the hot hardness. As such, the cutting edges on tools made from M42 super high speed steel stay sharp and hard in heavy-duty and high-production cutting applications.

Applications:

AISI M42 tool steel is a high-speed steel suitable for cutting tools such as, twist drills, broaches, taps, milling, cutters, saws, reamers etc. In terms of performance, HSS grade M42 is a steel to be used in conditions where the demand for hot hardness is of great importance i.e. where high performance is essential.

Quick Detail:M42---Flat Bars 

COMPOSITION

RELATIVE PROPERTIES

HEAT TREATING INSTRUCTIONS： HARDENING

Quenching:Pressurized gas, warm oil, or salt. For pressurized gas, a rapid quench rate to below 1000°F (538°C) 

is critical to obtain the desired properties. For oil, quench until black, 

about 900°F (482°C), then cool in still air to 150 -125°F (66-51°C). For salt maintained at 1000-1100°F (538-593°C), 

equalize, then cool in still air to 150 -125°F (66-51°C).

Tempering:Temper immediately after quenching. Typical tempering range is 1025-1050°F (552-566°C).

Hold at temperature for 2 hours, then air cool to ambient temperature. Double tempering is required. 

For large cross sections, and especially for blanks from which tools will be cut by wire EDM, 

triple tempering is strongly recommended.

Advantage:

all-round applicability

good machine-ability

good performance

good hot hardness

good wear resistance

Common M42 Tool Steel Related Specifications and M42 High Speed Steel Equivalents