· KAIPU Engineering · materials-encyclopedia · 1 min read
17-4 PH Precipitation-Hardening Martensitic Stainless Steel
Materials encyclopedia entry for 17-4PH.
17-4 PH Precipitation-Hardening Martensitic Stainless Steel is a reference entry for industrial cutting tools and blades. The composition, hardness, heat treatment and application guidance are summarised below for engineering reference.
Standard composition: C ≤ 0.07 %, Cr 15.0–17.5 %, Ni 3.0–5.0 %, Cu 3.0–5.0 %, Nb 0.15–0.45 %, Mn ≤ 1.00 %, Si ≤ 1.00 %, balance Fe
Hardness: Solution annealed HB 320; aged to HRC 40–44 (H900), 36–40 (H1025), 28–32 (H1150)
Heat treatment: Solution anneal 1,040 °C, age at 480–620 °C for 1–4 h depending on target hardness
Properties: A precipitation-hardening stainless. Achieves high strength (1,300 MPa UTS) and good corrosion resistance. The “H900” condition gives the highest hardness; “H1150” gives the best toughness. Used for high-strength structural blades and dies.
Applications: Aerospace structural blades, die-casting dies, plastic-injection moulds, food-processing parts requiring high strength + corrosion resistance.
Cross-reference: ≈ DIN 1.4542, GB 05Cr17Ni4Cu4Nb, AISI 630.
See also: D2 vs SKD11 comparison, Material Grade Converter, The KAIPU 5-Factor Blade Selection Framework.