carbide insert selection guide for turning. Complete reference tables for engineering decisions.
Complete reference tables and engineering data for full grade chart. All values verified against ISO, ANSI, and manufacturer standards.
Carbide grades are classified by ISO application groups (P, M, K, N, S, H) based on the material they are designed to cut. Within each group, grades range from tough (lower numbers, e.g., P10) to hard/wear-resistant (higher numbers, e.g., P50). This guide helps navigate the grade designations across major manufacturers.
Use ISO classification as the common language. Start with the ISO code (e.g., P20-P30 for general steel turning). Each manufacturer has grades targeting that range. Sandvik GC4325, Kennametal KCP25B, and Iscar IC8250 are all P25-class general steel grades. They are functionally similar but not identical -- always test before changing suppliers.
Tough grades (higher cobalt binder, larger grain size) resist impact and thermal shock. Use for roughing, interrupted cuts, and unstable setups. Hard grades (lower cobalt, finer grain) resist wear and deformation. Use for finishing, high-speed continuous cuts, and abrasive materials. Start with the manufacturer's "first choice" grade for your material.
CVD (Chemical Vapour Deposition): thicker coatings (5-12 um), deposited at high temperature. Best for steel turning where heat resistance matters. PVD (Physical Vapour Deposition): thinner (2-5 um), deposited at lower temperature, sharper edges. Best for milling, stainless, superalloys, and sharp cutting edges. CVD is generally tougher; PVD keeps a sharper edge.
Use this reference to navigate carbide grade designations. Start with the material's ISO group (P/M/K/N/S/H), then select a grade based on the operation (finishing vs roughing). When cross-referencing, compare the ISO classification ranges, not just the manufacturer's marketing name.
Continue with closely related resources from the machining reference library.
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