Meaning
High carbon high chromium alloyed tool material categorized under AISI designation as cold work steel d2 provides exceptional wear resistance through high volume fraction of primary carbides. Chromium content reaches twelve percent alongside substantial carbon additions near one point five percent, establishing a microstructure dominated by hard carbide particles embedded in a tempered martensitic matrix. Dimensional stability during thermal treatment remains superior compared to lower alloy grades, rendering the composition suitable for long production run tooling applications where abrasive wear dominates service conditions.
Alloy Composition
Metallurgical formulation balances high carbon additions with generous carbide formers to maximize wear performance in industrial tooling. Vanadium and molybdenum elements supplement the primary chromium concentration, refining grain boundaries and enhancing secondary hardening response during high temperature tempering cycles. Carbide distribution directly dictates the service life of stamping dies and slitting cutters, demanding careful control during primary casting and secondary hot working operations.
Thermal Processing
Heat treatment protocols dictate final hardness levels and fracture toughness characteristics through controlled austenitizing and multi stage tempering sequences. Vacuum furnaces typically heat components above one thousand degrees Celsius followed by rapid gas quenching to transform austenite into untempered martensite. Retained austenite percentages require cryogenic cooling steps to ensure dimensional constancy before final tempering operations achieve working hardness values near sixty Rockwell C.
Tooling Performance
Machining and grinding difficulties arise directly from the carbide rich microstructure, requiring specialized abrasive wheels and rigid setup conditions during finishing operations. Compressive strength supports heavy blanking duties on abrasive sheet metals without suffering premature edge chipping or plastic deformation under high tonnage presses. Procurement specialists evaluate this grade against powder metallurgy alternatives when balancing tooling costs with expected production volumes in stamping operations.
