High-speed tool steel: T4 Executive standard: ASTM A600-1992a ASTM T4 is a tungsten-based general cobalt-containing high-speed steel. Compared with W18Cr4V, the red hardness and high temperature hardness are slightly higher, but the toughness is low. After quenching, the surface hardness can reach 63-66HRC. Used as high-speed cutting tools, automatic machine tools, for cutting higher-strength materials. Carbon C: 0.70～0.80 (allowable deviation: ±0.01) Silicon Si: 0.20～0.40 (allowable deviation: ±0.05) Manganese Mn: 0.10～0.40 (allowable deviation: +0.04) Sulfur S: ≤0.030 Phosphorus P: ≤0.030 chromium Cr: 3.75～4.50 (allowable deviation: ±0.05) Nickel Ni: allowable residual content ≤0.30 Copper Cu: allowable residual content ≤0.25 Vanadium V: 0.80～1.20 (allowable deviation: ±0.05) Mo: 0.40～1.00 (allowable deviation : Size ≤ 6, ± 0.05; size> 6, ± 0.10) Tungsten W: 17.50 ~ 19.00 (allowable deviation: size ≤ 10, ± 0.10; size> 10, ± 0.20) Cobalt Co: 4.25 ~ 5.75 (allowable deviation: ± 0.15) Hardness: Delivery hardness: (other processing methods)≤285HB; (annealing)≤269HB. Sample heat treatment system and quenching and tempering hardness: ≥63HRC Heat treatment specification: quenching, 820～870℃ preheating, 1270～1290℃ (salt bath furnace) or 1280～1300℃ (box furnace) heating, oil cooling, 540～ Temper 2 times at 560℃, 2h each time. Hot-rolled, forged, and cold-drawn steel bars are delivered in annealed state, and hot-rolled and forged steel bars are delivered after processing by annealing + other processing methods (skinning, light drawing, polishing or polishing, etc.).
Link to this article：What is T4 steel? What are the application areas of T4 steel?
Reprint Statement: If there are no special instructions, all articles on this site are original. Please indicate the source for reprinting:Alloy Wiki，thanks