Heat Treatment of Strut Bearings: How Quenching and Tempering Decide Life

Heat Treatment Is the Core

Same steel, different heat treatment - life can differ several times. The goal: hard outside, tough inside, dimensionally stable.

Key Steps

• Quenching: Heat to 830-860C, fast cool to form hard martensite
• Tempering: 150-180C low temper reduces brittleness and stabilizes structure
• Cold treatment: -60C deep cold lowers retained austenite for precision parts

Hardness vs Toughness

Too hard chips; too soft dents the raceway and pits early. Rings HRC60-64 and balls HRC62-66 are typical.

Distortion Control

• Loading pattern and heating rate matter
• Uneven cooling causes ovality and warp
• Grinding after heat treatment corrects size and form

Verification

• Hardness gradient testing
• Metallography for structure grade
• Batch distortion sampling

Huami follows a heat-treat process card and keeps metallography reports for batch consistency.