000146648 001__ 146648
000146648 005__ 20180913055655.0
000146648 037__ $$aCONF
000146648 245__ $$aNd:YAG laser joining between stainless steel and nickel-titanium shape memory alloys
000146648 336__ $$aConference Papers
000146648 520__ $$aNickel-Titanium (NiTi) shape memory alloys are often used in medical component devices, for instance as guide wires for neurological surgery applications. The manufacture of such devices becomes more and more challenging, especially considering the need to join them with other metals. Laser welding is a promising technique to realize and to guaranty the mechanical stability of dissimilar metal welds, although inherent differences in chemical compositions, absorption, physical and thermo-mechanical properties can lead to severe problems, in particular fracture of the weld due to the possible formation of brittle intermediate phases. Laser welds of NiTi - stainless steel (SS) pieces have been made with a Nd:YAG laser and the weld microstructure have been studied by Scanning Electron Microscopy (SEM). The phases and defects in these welds have been compared with those observed in autogenous NiTi welds and SS welds. They have been put into relation with the Fe-Ni-Ti ternary phase diagram. In addition, Differential Thermal Analyses (DTA) of NiTi-SS alloys and NiTi-SS diffusion couple experiments have been performed in order to gain a better understanding of the phases and reactions occurring during laser welding. This diffusive couple experiments have been analyzed by Energy Dispersive X-ray Spectroscopy (EDX) It appeared that although experiments were performed under controlled atmosphere, oxide layers have restrained the chemical diffusion of concerned elements. Further diffusion couple experiments will be realized with stainless steel welded caps to avoid oxygen contamination during heating.
000146648 700__ $$0242216$$aVannod, J.$$g148019
000146648 700__ $$0242214$$aHessler-Wyser, A.$$g104267
000146648 700__ $$aRappaz, M.
000146648 7112_ $$a14th European Microscopy Congress$$cAachen$$dSeptember 1-5, 2008
000146648 909C0 $$0252025$$pCIME$$xU10192
000146648 909CO $$ooai:infoscience.tind.io:146648$$pconf$$pSB
000146648 937__ $$aCIME-CONF-2010-007
000146648 973__ $$aEPFL$$rREVIEWED$$sPUBLISHED
000146648 980__ $$aCONF