ISO 15608 – A Welder's Guide to Material Grouping

 

Making Sense of ISO 15608 – A Welder's Guide to Material Grouping

If you've ever been involved in welding qualifications, you’ve probably heard of ISO 15608. But what does it really mean in day-to-day welding work?

Let’s break it down in simple terms.

---

What is ISO 15608?

ISO 15608 is a guideline that helps welding engineers, inspectors, and fabricators group different types of metals based on how similar they are when it comes to welding.

Why group materials? Because not every metal welds the same way — and qualifying a welding procedure or a welder for each metal separately would be a nightmare. This standard saves time, money, and effort by grouping similar materials together so one qualification can cover many.

---

Why It Matters

Think of it like this — if a welder is qualified to weld one type of stainless steel, they might also be good to weld another similar one. ISO 15608 helps us prove that without having to redo the whole testing process.

It’s widely used in:

• Welding procedure qualifications (WPS / PQR)

• Welder qualifications (WPQ)

• Inspection and certification audits (like ISO 3834)

   

  The Main Material Groups

  Here’s a quick snapshot of how ISO 15608 categorizes materials:

  Group	Material
  1	Mild steel & fine-grain structural steels
  2	Ferritic cast steels
  3	Low-alloy steels (Cr <6%)
  4	Austenitic stainless steels
  5	Duplex & super duplex steels
  6	Heat-resistant stainless steels
  7	Nickel-chromium steels
  8	Aluminium and its alloys
  9	Magnesium alloys
  10	Nickel and nickel alloys
  11	Copper and copper alloys
  12	Titanium and titanium alloys
  13	Zirconium alloys
  14	Other reactive/refractory metals
  41–48	Special groups like cast irons, tool steels, etc.

   

  The Real-World Benefit

  For companies and welders, this means:

• Less testing

• More flexibility

• Faster project approvals

• Better international recognition

Whether you're qualifying welders for stainless steel pipelines or developing procedures for aluminium tank fabrication, ISO 15608 gives you a roadmap to do it smartly and efficiently.

At TRINITY NDT, We Make Standards Work for You

Need help navigating ISO 15608, welder certifications, or welding procedure qualifications?

We’ve helped hundreds of companies get certified, stay compliant, and work smarter. Reach out to us today — we're just a call or click away.

Ravi & Shiva – TRINITY NDT WELDSOLUTIONS PVT. LTD.

---