首页|Microstructure,mechanical and fracture properties of friction stir welded 2195 Al-Li alloy joints

Microstructure,mechanical and fracture properties of friction stir welded 2195 Al-Li alloy joints

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
  • 维普
The 8 mm-thick 2195 Al-Li alloy joints were achieved by Friction Stir Welding(FSW).The microstructural evolution,temperature-dependent mechanical properties,and fracture proper-ties were studied.The Ti,δ'/β'and θ'precipitates were observed in the Base Metal(BM)and the Heat Affected Zone(HAZ).Most of the precipitates,except for re-precipitated δ'/β'phases,were dissolved in the Nugget Zone(NZ).The tensile specimens that failed at cryogenic temperatures(-196 ℃)had the maximum Ultimate Tensile Strength(UTS),and the fracture surface showed the inter-granular fracture characteristics.Compared to those at room temperature(25 ℃),the decreasing tensile properties at high temperature(180 ℃)were related to microstructure and strain hardening effects.The NZ presented the optimal fracture toughness,and the Crack Tip Opening Displacement(CTOD)was mutually dominated by microhardness and grain size.Analysis on Fati-gue Crack Growth(FCG)rates indicates that the Thermal-Mechanically Affected Zone(TMAZ)exhibited the most superior fatigue resistance performance at stress intensity range below 17 MPa.m1/2 due to compressive residual stress and the crack closure effect.The fatigue fracture surfaces reveal that the crack propagation zone was characterized by the striations and secondary cracks.Also,inter-granular fracture behavior was responsible for the fastest FCG rates in the NZ.

Aluminum alloysFriction stir weldingMicrostructural evolutionMechanical propertiesFracture mechanism

Guangda SUN、Weizhao SUN、Li ZHOU、Sanfeng LUO、Zili ZHANG、Debo LIU、Huiqiang WU

展开 >

State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China

Shandong Provincial Key Laboratory of Special Welding Technology,Harbin Institute of Technology(Weihai),Weihai 264209,China

Beijing Institute of Astronautical Systems Engineering,Beijing 100076,China

National Key Research and Development Program of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of China

2020YFA0711101U183720451974100

2024

10.1016/j.cja.2023.10.017

中国航空学报(英文版)
中国航空学会

中国航空学报(英文版)

CSTPCDEI
影响因子：0.847
ISSN：1000-9361
年,卷(期)：2024.37(1)
  • 48