Read the condition
Quenched and tempered (+QT) describes a final condition; surface hardened describes a different treatment objective. Core strength, case depth and surface hardness must be specified separately. A grade name cannot establish the treatment achieved on a finished component.
Design and processing
Section size, hardenability, quench method and tempering influence the final properties. Machining allowance and distortion control should be agreed before treatment. Do not publish a universal furnace recipe without the part geometry and qualified process.
Certificate review
Confirm the current product specification, grade, section or ruling thickness, heat-treatment record and required tests. Historical EN 10083 references must be checked for their applicable successor or project edition. Magnetic particle, ultrasonic and hardness requirements should be stated where needed.
Information to record
- Exact product standard and edition; approved drawing or specification revision.
- Grade, dimensions, final condition and heat-to-piece traceability.
- Acceptance test, inspection document and responsible approving party.
Frequently asked questions
Does a high surface hardness prove adequate core toughness?
No. Surface hardness and core mechanical properties need their own specified acceptance evidence.
Sources and reference scope
- Procurement and editorial guidance — Cross-checked against product terminology and the cited material rules
Guidance describes checks to request. It is not a claim of available stock, certificates or completed project engineering. - 钢材产品简介 — Slides 3, 5–6, 15–19
Product forms, units and grade vocabulary; not proof of current stock or class certification.