焼結低合金鋼の超強靭化に向けた拡散特性の解析とメゾヘテロ組織制御

超强烧结低合金钢扩散性能分析及细观异质结构控制

• 批准号: 14750589
• 负责人: 松田 光弘
• 金额: $ 1.79万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14750589/
• 关键词: Metal Infection Molding; Low alloy steels; Heterogeneous microstructure; Mechanical properties; Mechanical alloying; metal injection molding; low alloy steels; Mo content; heterogeneous microstructure; mechanical properties; PCPS

筆者らはこれまでに金属粉末射出成形(MIM)法によるFe-6Ni-0.5Mo-0.4C(mass%)合金の熱処理材において,引張強度が約2000MPaで伸びは5%を示すなど超強靭な特性を示すことを報告した.これは基地自体が固溶強化したことに加え,NiやMoの偏析による白色部組織を網目状に焼戻しマルテンサイト相が取り囲んだ微細な不均質(メゾヘテロ)組織に起因したものであった.従って,このメゾヘテロ組織の最適化を図れば,さらなる高強度化,高性能化につながるものと考えられる.本研究では,不均質組織を担う白色部組織が基地中に均一に分散するように,新たに粉末の製造,混合および合成方法を取り入れるとともに白色部組織内における各種合金元素の拡散特性の制御を行うことで超強靭な焼結材料の創製を試みた.研究結果を以下に示す.(1)添加合金元素であるNiならびにMoを基地中へより拡散させるため,各種元素粉末にメカニカルアロイングを施してMIM材を作製した結果,白色部組織内に流出孔は形成せず,引張強度1756MPa,伸び2.2%とMo粉末を単独で添加したMIM(2%Mo添加)材(引張強度1563MPa,伸び2.6%)と比較して優れた値を示した.しかしながら,粉末の酸化による密度の低下ならびに残留オーステナイト量の増加により,上記0.5%Mo添加材の高性能化にはつながらなかった.(2)高密度化を達成するため,微細なカーボニル鉄粉(平均粒径:1.8μm)を用いてMIM材を作製した結果,相対密度が約1%上昇し,引張強度1965MPa,伸び4.9%と優れた特性を示した.本試料は相対密度が96%と高密度であることから,焼結材料にとって重要な指標である疲労特性に優れるものと期待できる.以上のことから,焼結低合金鋼のさらなる高強度化・高性能化には,メゾヘテロ組織を構成する元素の種類,濃度勾配および分散度合を制御するとともに焼結密度を上昇させる等,組織制御に関する基本指針が得られた.

The tensile strength of Fe-6Ni-0.5Mo-0.4C(mass%) alloy heat treated by MIM method is about 2000MPa and the elongation is about 5%. The base itself is solid-solution strengthened,Ni Mo segregation, white part organization, mesh-like structure, fine heterogeneous structure, etc. In addition, the optimization of the organization of the project is planned to be carried out in a high-intensity and high-performance manner. In this study, the heterogeneous structure, white part organization, uniform dispersion in the base, new powder production, mixing and synthesis methods, introduction into the white part organization, control of dispersion characteristics of various alloying elements, and creation of super strong sintered materials were studied. The results of the study are shown below. (1)As a result of the addition of alloying elements Ni and Mo to MIM(2%Mo) materials, outflow pores were formed in the white part of the structure, tensile strength 1756MPa, elongation 2.2% and tensile strength 1563MPa, elongation 2.6% respectively. The density of the acidified powder is low and the residual amount is increased. The high performance of the 0.5%Mo additive is recorded above. (2)High density was achieved by using MIM as a raw material. As a result, the relative density increased by about 1%, tensile strength was 1965MPa, elongation was 4.9%, and excellent properties were demonstrated. This sample has a relative density of 96% and a high density. The above problems are solved by improving the strength and performance of sintered low alloy steel, improving the composition of elements, improving the concentration and dispersion of sintered low alloy steel, and improving the sintering density of sintered low alloy steel.

项目成果

M.Matsuda: "Development of High Strength Mg Alloys by MA-HDH P/M Process"Materials Science Forum. Vols.419-422. 739-744 (2003)

M.Matsuda：“通过 MA-HDH P/M 工艺开发高强度镁合金”材料科学论坛。

Dislocation Structure in Rapidly Solidified Mg97Zn1Y2 Alloy with Loge Period Stacking Order Phase

Loge周期叠序相快凝固Mg97Zn1Y2合金的位错结构

• 发表时间: 2005
• 期刊: Materials Transactions Vol.46, No.2
• 作者: M.Matsuda;M.Matsuda
• 通讯作者: M.Matsuda

Variation of long-period stacking order structures in rapidly solidified Mg97Zn1Y2 alloy

• DOI: 10.1016/j.msea.2004.10.040
• 发表时间: 2005-02-25
• 期刊: MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
• 影响因子: 6.4
• 作者: Matsuda, M;Ii, S;Nishida, M
• 通讯作者: Nishida, M

M.Matsuda: "Mechanical properties of injection molded Fe-6%Ni-0.4%C steels with varying Mo contents of 0.5 to 2%"METALS AND MATERIALS INTERNATIONAL. Vol.9 No.6. 537-542 (2003)

M.Matsuda:%20"机械%20属性%20of%20注射%20模制%20Fe-6%Ni-0.4%C%20钢%20与%20变化%20Mo%20含量%20of%200.5%20至%202%"金属%20AND%

Interaction between long period stacking order phase and deformation twin in rapidly solidified Mg97Zn1Y2 alloy

• DOI: 10.1016/j.msea.2004.08.006
• 发表时间: 2004-11-25
• 期刊: MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
• 影响因子: 6.4
• 作者: Matsuda, M;Ii, S;Nishida, M
• 通讯作者: Nishida, M