Overview
ISO 14590:2016 - Cold-reduced steel sheet of high tensile strength and low yield point with improved formability - defines requirements for commercially available cold‑reduced sheet steels engineered for a combination of high tensile strength, low yield point and enhanced formability. The standard covers two product types: Type 1 (specified to mechanical properties only) and Type 2 (specified to both chemical and mechanical properties). Bake hardening grades are included in both types.
Key scope points:
- Thickness range: 0.25 mm to 3.2 mm; widths 600 mm and over (coils or cut lengths).
- Excludes commercial/drawing qualities (ISO 3574), structural quality (ISO 4997) and higher-strength improved formability steels (ISO 13887).
Key topics and requirements
ISO 14590:2016 sets out technical and quality requirements including:
- Chemical composition: Heat analysis and product analysis limits for Type 2 grades (including SS, DP and BH families) and limits on additional alloying elements (Cu, Ni, Cr, Mo, Nb, V, Ti).
- Mechanical properties: Defined tensile, yield and elongation requirements given in the standard’s tables for Type 1 and Type 2 grades.
- Testing and sampling: Tensile testing procedures and sampling rules (see Clauses 6–8); tensile testing referenced to ISO 6892‑1.
- Bake hardening: Special bake‑hardening test method (Annex A) - includes the strain/heat treatment cycle used to measure BH response (definitions reference 170 °C for 20 min).
- Manufacture & surface requirements: Manufacturer’s discretion on making steel, with purchaser entitlements for process information; surface condition, finish, oiling, coil size, dimensional and shape tolerances (reference ISO 16162).
- Inspection and marking: Requirements for inspection, acceptance, marking and information to be supplied by the purchaser.
Practical applications and users
Who uses ISO 14590:2016:
- Steel producers and rolling mills specifying cold‑reduced sheet with improved formability.
- Automotive and appliance OEMs and Tier suppliers specifying sheet steels for formed components where low yield point and bake hardening are important.
- Fabricators and stampers that require predictable formability and post‑paint bake performance.
- Purchasing/specification engineers, testing laboratories and quality inspectors verifying chemical and mechanical conformity.
Practical benefits:
- Ensures consistent formability and strength for deep‑drawn or complex stamped parts.
- Provides standardized test methods and reporting for procurement and quality control.
- Controls ageing and bake‑hardening behavior important to paint bake cycles.
Related standards