WPS Material – Full Form, Hardness & Temperature Guide

WPS material is a critical concept in welding and heat treatment industries. It directly affects hardness, strength, and reliability of welded components used in heavy engineering, automotive, and fabrication sectors.

For professional solutions, explore our heat treatment services for precise hardness control.

WPS Full Form

WPS stands for Welding Procedure Specification. It is a formal document that defines how welding should be performed to ensure consistent quality and mechanical performance. :contentReference[oaicite:0]{index=0}

It includes:

• Material type
• Heat input
• Preheat temperature
• Interpass temperature
• Post Weld Heat Treatment (PWHT)

A WPS is always supported by a PQR (Procedure Qualification Record), which verifies that the process produces acceptable results. :contentReference[oaicite:1]{index=1}

What Is WPS Material?

WPS material refers to the base metal and filler metal used under a specific welding procedure, along with its acceptable hardness range after welding.

The goal is to ensure:

• Controlled hardness
• Proper strength
• Resistance to cracking
• Long-term durability

Hardness is especially critical in the Heat Affected Zone (HAZ), where rapid heating and cooling can increase brittleness. :contentReference[oaicite:2]{index=2}

WPS Material Hardness (HRC Table)

Material Type	Hardness (HRC)	Application
Mild Steel (MS)	15 – 25 HRC	General fabrication
Alloy Steel	25 – 45 HRC	Automotive & shafts
Tool Steel (D2 / WPS Type)	36 – 54 HRC	Dies & cutting tools
Hardened Components	50 – 65 HRC	Wear-resistant parts

For example, mild steel typically ranges between 15–25 HRC in untreated condition. :contentReference[oaicite:3]{index=3}

WPS Heat Treatment Temperature Chart

Process	Temperature Range (°C)	Purpose
Preheating	100 – 300°C	Reduce cooling rate
Hardening	800 – 1050°C	Increase hardness
Tempering	150 – 650°C	Reduce brittleness
Stress Relieving (PWHT)	500 – 700°C	Reduce residual stress

These temperatures are defined in WPS to control heat input and avoid defects like cracking or excessive hardness. :contentReference[oaicite:4]{index=4}

Zones of Hardness in WPS

1. Weld Metal

Ensures proper strength and bonding.

2. Heat Affected Zone (HAZ)

Most critical zone where hardness peaks and cracks may occur.

3. Base Metal

Ensures original material properties are maintained.

Case Study 1: Weld Cracking Due to High Hardness

A fabrication company faced repeated weld failures in heavy structures.

Problem: High HAZ hardness caused brittle cracks

Solution:

• Controlled preheating
• Applied PWHT at 600°C

Result:

• Reduced hardness
• Zero cracking
• Improved weld life

Case Study 2: Tool Steel (WPS Type) Performance

A die manufacturing unit using WPS-grade tool steel faced rapid wear.

Solution:

• Optimized hardening at 1020°C
• Double tempering at 550°C

Result:

• 50% increase in tool life
• Improved hardness consistency

Best Practices for WPS Material Control

• Maintain proper preheat temperature
• Control heat input
• Use low hydrogen electrodes
• Apply PWHT when required
• Perform hardness testing (HRC/HV)

Internal Resources

• Annealing Process
• Hardening Process
• Tempering Process
• EN24 Hardness Guide

Conclusion

WPS material is not just about welding—it is about controlling hardness, temperature, and metallurgical properties to ensure safety and durability. Proper WPS implementation prevents failures, improves performance, and ensures long-term reliability.