CARBURIZED COMPONENT AND METHOD OF MANUFACTURING THE SAME

• Main Authors: MATSUMURA KOJI, MORITA TOSHIYUKI, ANDO TOMOHIRO, UMEMORI NAOKI
• Format: Patent
• Language: English; Japanese
• Published: 15.12.2014
• Subjects: ALLOYS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PROBLEM TO BE SOLVED: To provide a carburized component having excellent fatigue characteristics to both of low load input and high load input.SOLUTION: The carburized component is obtained by working steel into a component shape and carburizing the steel, the steel containing, by mass%, C:0.10 to 0.40%, Si:0.05 to 2.00%, Mn:0.30 to 2.00%, Cr:0.30 to 3.00%, N:0.025% or less, and one or more kind of Al:0.020 to 0.100%, Nb:0.01 to 0.20%, Ti:0.005 to 0.20% as pinning grain forming elements which form pinning grains by nitridation, and the balance Fe with inevitable impurities. In the carburized component, the grain size number of a crystal grain present in a component surface 50 μm or more deep from a surface is more than 5 and the grain size number of a crystal grain present in component inside 3 mm or more inner from the surface is 5 or less. 【課題】低荷重の入力及び高荷重の入力の何れにも優れた疲労特性を有する浸炭部品を提供する。【解決手段】質量％でＣ：0.10〜0.40％，Si：0.05〜2.00％，Mn：0.30〜2.00％，Cr：0.30〜3.00％，Ｎ：0.025％以下、窒化によりピン止め粒子を形成するピン止め粒子形成元素として、Al：0.020〜0.100％，Nb：0.01〜0.20％，Ti：0.005〜0.20％のうちの１種若しくは２種以上を含有し、残部Fe及び不可避的不純物の組成を有する鋼を部品形状に加工し、浸炭処理して成る浸炭部品を、表面から５０μｍ以内の部品表層の結晶粒度番号が５番より上で、表面から３ｍｍ以上の部品内部の結晶粒度番号が５番以下であるようにする。【選択図】 なし