PROBLEM TO BE SOLVED: To provide: a high strength titanium alloy member made of an α-β titanium alloy, capable of obtaining high strength and high durability not only on a surface but also over the whole of the inside of the member, imparted with a large and deep compressive residual stress in the vicinity of the surface, and excellent in fatigue resistance； and a method for producing the high strength titanium alloy member.SOLUTION: The method for producing a high strength titanium alloy member includes: a step of preparing a raw material comprising a titanium alloy； a nitridation step of forming a nitride compound layer and/or a nitrogen solid solution layer on a surface layer of the raw material by nitriding to produce a nitrogen-containing raw material； a mixing step of mixing the raw material with the nitrogen-containing raw material to obtain a nitrogen-containing mixed material； a sintering step of bonding the materials in the nitrogen-containing mixed material to each other and dispersing nitrogen included in the nitrogen-containing raw material uniformly in the form of a solid solution in the whole of the inside of a sintered titanium alloy member to obtain the sintered titanium alloy member； a hot plastic working step of performing hot plastic working to the sintered titanium alloy member to obtain a processing member and/or a heat treatment step of performing heat treatment to the sintered titanium alloy member to obtain a processing member； and a surface treatment step of imparting a compressive residual stress to the processing member.【課題】α－β型チタン合金の部材において、表面のみならず部材内部全体に亘って高強度かつ高耐力を得るとともに表面近傍に大きく深い圧縮残留応力を付与した、耐疲労性に優れた高強度チタン合金部材およびその製造方法を提供する。【解決手段】チタン合金からなる原材料の準備工程と、窒化処理により原材料の表層に窒素化合物層および／または窒素固溶層を形成して窒素含有原材料を作製する窒化工程と、原材料と窒素含有原材料とを混合して窒素含有混合材料を得る混合工程と、窒素含有混合材料の材料同士を接合するとともに窒素含有原材料に含まれる窒素を内部全体に亘って固溶した状態で均一に分散させて焼結チタン合金部材を得る焼結工程と、焼結チタン合金部材に熱間塑性加工を施して処理部材を得る熱間塑性加工工程および／または焼結チタン合金部材に熱処理を施して処理部材を得る熱処理工程と、処理部材に圧縮残留応力を付与する表面処理工程を備える。【選択図】なし
