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12 <strong>Wear</strong> resistance Cermet Natural diamond Hard materials / carbide PCD Diamond coated CBN Ceramic (O) Ceramic (N) What is carbide? Cemented carbide HSS Toughness Carbide is a brittle, hard material with mechanical properties that can be adjusted within a very wide range, given its composition and microstructure. The hardness and toughness range of the CERATIZIT grades includes everything from wear resistant tool steel to super-hard ceramic materials. Carbide is a powder metallurgically produced composite material consisting of a hard material (e.g. tungsten carbide, WC) and a metallic binder (e.g. cobalt, Co) The hard material provides the necessary → hardness → wear resistance The metallic binder provides → toughness Carbide properties depending on the Co contents and WC grain size Cobalt content ↑↑ Grain size ↓↓ T.R.S. High hardness (= wear resistance) WC Co WC Micrograph of WC-Co carbide Cobalt content ↓↓ Grain size ↓↓ Fracture toughness Cobalt content ↑↑ Grain size ↑↑
The basis for optimum quality The graphic illustrations below show that the mechanical properties of the carbide mainly depend on the binder content (Co) and the TC grain size. Hardness, i.e. wear resistance, increases inversely/reciprocally proportional to the fracture toughness. This means that the harder the material the more it reacts to notch tensions and impact stress (the ‘impact resistance’ parameter, which cannot be precisely defined, correlates to a high degree with the fracture toughness of the material). On the other hand, the transverse rupture strength does not directly depend on the hardness but rather on the TC grain size and the cobalt content. The adhesive wear (tendency to stick), however, decreases with the grain size and the cobalt content of the carbide used. The list of the mentioned interdependencies, which could be extended at will for other wear and failure mechanisms, show that it is only possible to choose the correct carbide grade following a systematic procedure and/or based on experience with similar forming processes. Submicron grain Fine / medium grain Coarse grain Hardness [HV30] Transverse rupture strength [MPa] Toughness K IC-value [MPa*m 1/2 ] Submicron grain Fine / medium grain Coarse grain Submicron grain Fine / medium grain Coarse grain Submicron grain Fine / medium grain Coarse grain 13
Page 1 and 2: Wear parts
Page 3 and 4: CERATIZIT - other production sites
Page 5 and 6: Wear parts for industrial applicati
Page 7 and 8: Competence and know-how At CERATIZI
Page 9 and 10: Manufacture and machining of blanks
Page 11: Composite parts For several applica
Page 15 and 16: CT grade code Grade characteristics
Page 17 and 18: Si 3 N 4 for cutting tools Si 3 N 4
Page 19 and 20: Roughness and surface Table for the
Page 21 and 22: September M D M D F S S 29 30 31 1
Page 23 and 24: Headquarters: CERATIZIT S.A. Main s

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