AISI H13 Hot Work Tool Steel

• HOT ROLL FINISH
• Machine finish) FOUR SIDES

DESCRIPTION

Combines good red hardness and abrasion resistance with the ability to resist heat checking. The most widely used hot work tool steel for aluminum and zinc die casting dies. Popular for extrusion press tooling because of its ability to withstand drastic cooling from high operating temperatures.

ADVANTAGES

• High resistance to heat checking
• Good red hardness
• Good shock resistance
• Good machinability
• Good dimensional stability
• Excellent hardenability

TYPICAL ANALYSIS

CARBON…………0.40 CHROMIUM ……….5.25 SILICON …………1.00

MOLYBDENUM ..1.25 VANADIUM ……….1.05

HEAT TREATMENT

FORGING ………………………………..2050°F to 2150°F, stop at 1650°F and cool slowly

ANNEALING ……………………………1600°F, furnace cool. Brinell 207 max

PREHEATING ……………………………1350°F soak before heating, for hardening

HARDENING …………………………….1850 °F, air quench to 150°F

TEMPERING ……………………………...1050° to 1150°F, average Rockwell C-38/46; die casting dies

should be hardened to Rockwell C-44/48. Double temper

recommended.

MACHINABILITY

May be machined without difficulty in the thoroughly annealed condition. Has a rating of 75 as compared with a one percent carbon tool steel, which has a rating of 100.

DIMENSIONAL STABILITY

Generally expands 0.001 in./in. of cross section when air quenched from the proper hardening temperature.

HARDENING

In a controlled atmosphere, preheat thoroughly at 1300° to 1400° F and hold for one hour per inch of greatest cross section. Quench in still air and temper immediately. May be oil quenched when maximum hardness is the primary requirement.

Note: When oil quenched, this grade is as vulnerable to cracking and has the same distortional characteristics as an oil hardening tool steel.

Specimens 1 in. round by 3 in. long were preheated at 1350° F. They were then transferred to a high-heat furnace and air-quenched from various temperatures ranging form 1750° to 2000° F.

TEMPERING RESULTS – DOUBLE TEMPER RECOMMENDED

Hardness tests were made on 1 in. round specimens which were air quenched from 1950° F and tempered for two hours at various temperatures. Results may be used as a tempering guide, keeping in mind that tools of heavy section or mass may be several points lower in Rockwell hardness for a given treatment.