How to Determine the Tempering Temperature of H Material

For H13 material, the ideal tempering temperature is between 550 and 600°C. This is a crucial process parameter to guaranty that its toughness is good, its microstructure is consistent, and its hardness is between 48 and 52 HRC. This range of temperatures successfully reduces quenching stress, avoids cracking, and produces outstanding overall performance.

 

1. Foundation for Tempering Temperature Setting

Logic for Selecting the Target Temperature

Get Rid of Remaining Stress

To completely release the tremendous internal stress caused by quenching, temperatures above 550°C are required.

Maintain Microstructure Stability

Make uniform tempered martensite out of unstable quenched martensite.

Regulate the Hardness

After quenching, adjust the overly high hardness (perhaps >55 HRC) to the optimal range of 48–52 HRC.

Boost Your Toughness

To satisfy mold service requirements, increase impact resistance while retaining high strength.

580℃×2h×2 tempering cycles is the recommended procedure. Businesses in Wuhan have embraced this well-established approach, which stabilizes measured hardness at 49–51 HRC.

 

2. Temperature Deviation's Effect

<550°C: Workpiece prone to deformation or fracture, significant residual tension, insufficient stress release600°C: Strength and wear resistance are impaired because hardness decreases too quickly, probably below 48 HRC;

Batch consistency may be impacted by ±10°C fluctuation, which might result in hardness changes of 1-2 HRC.

Use a tempering furnace with a multi-point temperature measurement feature and a PID temperature control system to make sure the furnace temperature differential is ≤±5°C.

 

3. Useful Application Suggestions

To avoid stress rebound, the workpiece must cool to room temperature following the initial tempering;

The holding time can be suitably increased for thick workpieces (thickness > 100mm) (30 minutes for every 25mm of thickness);

Give local compliant service providers top priority. Wuhan Heat Treatment Plant and Jingmo Technology, for example, offer comprehensive furnace temperature profiles and hardness reports.

"Precise temperature control, accurate testing frequency, and verifiable data" are safety standards that guaranty each batch of H13 workpieces operates dependably.