Thermal processing and characterization of 316LVM cardiovascular stent.
In the current investigation, annealing was employed as a means to improve the mechanical performance of 316LVM coronary stents. Two different temperatures (1000 degrees C and 1150 degrees C) were explored for the thermal processing of the device. Acid pickling was done as a pre-annealing step to remove the debris and slag material attached to the stent after laser cutting. Post annealing operation involved the electrochemical polishing of the device which was also a parameter for assessment of the feasibility of the annealing process. Microstructural characterization, balloon expandability and tensile testing of the stents were performed to characterize the properties after thermal treatment. A fine grained austenitic structure with marked improvement in the % elongation (>40%) could be achieved after annealing the stents at 1000 degrees C. Balloon expandability tests of the stents annealed at 1000 degrees C indicated that the device was implantable.
Verma
Arpana
A
University of Arkansas, Fayetteville, AR 72701, USA.
Choubey
Animesh
A
Raval
Ankur
A
Kothwala
Devesh
D
D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry; D001807:Blood Vessel Prosthesis; D003331:Coronary Vessels; D008422:Materials Testing / Q000379:methods*; D013193:Stainless Steel / Q000032:analysis / Q000737:chemistry; D015607:Stents; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength
D001672:Biocompatible Materials; D013193:Stainless Steel