Material Of Jaw Plates Of Rock Jaw crusher

The jaw plates of a rock jaw crusher are crucial components that directly interact with the crushed material, so they must be made from highly wear-resistant and durable materials to withstand abrasion, impact, and compression forces. Common materials used include:

1. Manganese Steel (Hadfield Steel – ASTM A128)
– Grade: Typically Mn14%, Mn18%, or Mn22% (with 12-14% manganese, 1-1.4% carbon).
– Properties:
– Exceptional toughness and work-hardening ability (becomes harder under impact).
– Self-repairing surface due to hardening under pressure.
– Suitable for highly abrasive and hard rocks like granite, basalt, and quartz.
– Limitations: May deform under extreme loads if not properly heat-treated.

2. High Chrome Cast Iron (HCCI) / White Iron
– Grade: ASTM A532 Class III Type A (e.g., Cr20, Cr26, Cr28 with 2-3% carbon).
– Properties:
– Excellent abrasion resistance due to hard chromium carbides.
– More brittle than manganese steel but better for fine abrasive materials.
– Often used in secondary crushing or softer rocks.
– Limiions: Lower impact resistance; prone to cracking under heavy shocks.

3. Alloy Steel (Low/Medium Carbon Steel with Boron or Chromium)
– Used in less abrasive applications where cost is a concern.
– May be heat-treated for improved hardness.

4. Composite Materials (Ceramic Inserts or Bimetallic Plates)
– Combines a tough base (steel) with ultra-hard inserts (tungsten carbide or ceramic).
– Used in highly abrasive environments for extended lifespan.

Selection Factors:
– Rock Type: Harder rocks (granite, basalt) require manganese steel; softer materials may use high chrome iron.
– Crusher Type: Primary crushers need impact-resistant manganese steel; secondary/tertiary crushers may use high-chrome alloys.
– Cost vs. Lifespan: Manganese steel is more expensive but lasts longer in harsh conditions.

Additional Treatments:
– Hardfacing/Welding: Some plates are reinforced with wear-resistant welding layers.
– Heat Treatment: Enhances hardness and toughness.

For maximum durability in tough applications, Mn