HIGH STRENGTH TABULAR STEEL MATERIAL, MANUFACTURING METHOD THEREFOR AND DISCHARGE VALVE PART

• Main Authors: MATSUBAYASHI HIROYASU, YOSHIMURA YUTA, HIRAKAWA NAOKI, HIROTA RYUJI
• Format: Patent
• Language: English; Japanese
• Published: 28.04.2016
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PROBLEM TO BE SOLVED: To provide a tabular steel material high in impact fatigue characteristic suitable for a discharge valve part of a compressor.SOLUTION: There is provided a tabular steel material having a chemical composition containing, by mass%, C:0.010 to 0.200%, Si:0.05 to 1.00%, Mn:0.05 to 5.00%, Ni:1.00 to 6.00%, Cr:10.0 to 18.0%, N:0.010 to 0.200%, Mo:0 to 2.00%, Cu:0 to 4.00%, B:0 to 0.05% and the balance Fe with inevitable impurities with Cr equivalent, Ni equivalent and Ms point adjusted to predetermined ranges, a surface hardened layer with cross-section hardness in thick center part H(HV30) of 350 HV or more and difference between surface hardness H(HV0.01) and Hof 70 HV or more in Vickers hardness according to JIS Z2244:2009.SELECTED DRAWING: Figure 1 【課題】圧縮機の吐出弁部品に適した耐衝撃疲労特性の高い板状鋼材を提供する。【解決手段】質量％で、Ｃ：０.０１０〜０.２００％、Ｓｉ：０.０５〜１.００％、Ｍｎ：０.０５〜５.００％、Ｎｉ：１.００〜６.００％、Ｃｒ：１０.０〜１８.０％、Ｎ：０.０１０〜０.２００％、Ｍｏ：０〜２.００％、Ｃｕ：０〜４.００％、Ｂ：０〜０.０５％、残部Ｆｅおよび不可避的不純物からなり、Ｃｒ当量、Ｎｉ当量およびＭｓ点が所定範囲に調整された化学組成を有し、ＪＩＳ Ｚ２２４４：２００９に従うビッカース硬さにおいて、板厚中心部の断面硬さＨ0（ＨＶ３０）が３５０ＨＶ以上であり、表面硬さＨ1（ＨＶ０.０１）と前記Ｈ0の差が７０ＨＶ以上である表面硬化層を有する板状鋼材。【選択図】図１