Harmonic heterostructured pure Ti fabricated by laser powder bed fusion for excellent wear resistance via strength-plasticity synergy
通过激光粉末床熔合技术制备的谐波异质纯钛，通过强度-塑性协同作用实现优异的耐磨性
レーザードーズドベッドフュージョンによって製造されたハーモニックヘテロ構造の純チタンは、強度-塑性シナジーにより優れた耐摩耗性を実現
레이저 분말 베드 융합을 이용한 하모닉 헤테로구조 순수 티타늄, 강도-소성 시너지로 우수한 내마모성 달성
Harmonic heteroestructurado de Ti puro fabricado por fusión de lecho de polvo láser para excelente resistencia al desgaste mediante sinergia de resistencia-dureza
Titan pur à hétérostructure harmonique fabriqué par fusion de poudre laser pour une excellente résistance à l'usure grâce à la synergie résistance-déformation
Гармоничная гетероструктурированная чистая титановая конструкция, изготовленная методом лазерного спекания порошкового слоя, обеспечивает превосходную износостойкость за счет синергии прочности и пластичности
¹ State Key Laboratory of Precision Manufacturing for Extreme Service Performance, College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China
中国 长沙 中南大学机电工程学院 极端服役性能精准制造全国重点实验室
² Dundee International Institute, Central South University, Changsha 410083, China
中国 长沙 中南大学邓迪国际学院
³ Jiangxi Province Key Laboratory of Additive Manufacturing of Implantable Medical Device, Jiangxi University of Science and Technology, Nanchang 330013, China
中国 南昌 江西理工大学植入医疗器械增材制造江西省重点实验室
Titanium (Ti) is a promising candidate for biomedical implants due to lightweight, superior corrosion resistance and biocompatibility. Nevertheless, pure Ti is confronted with poor wear resistance which poses a profound bottleneck for orthopedic implant applications. In this work, a novel and feasible route of mechanical milling (MM) and laser powder bed fusion (LPBF) was first developed for architecting highly tunable heterostructure in pure Ti, aiming to overcome wear resistance dilemma.
During MM process, a spatial core-shell heterostructure within Ti particle was triggered by manipulating gradient and intense plastic deformation, accompanied with pre-existing dislocations. In subsequent LPBF process, the highly transient-melting kinetics and localized nature effectively perpetuated grain heterogeneity, hence creating a harmonic heterostructure within consolidated pure Ti. Consequently, the heterostructured Ti exhibited an excellent enhanced wear resistance (33.7%) compared to the homogeneous counterpart, which was attributed to a marvelous strength-plasticity synergy motivated by the hetero-deformation induced strengthening and strain-hardening.
Furthermore, back-stress caused by geometrical necessary dislocation pile-ups offset partial wear shear-stress, also contributing to wear resistance enhancement. This study not only provides a manoeuvrable and paradigm route to fabricate Ti with conspicuous strength-plasticity synergy and wear resistance, but also sheds light on developing and extending cutting-edge biomedical implant applications.
