Nanoindentation creep deformation behaviour of high nitrogen nickel-free austenitic stainless steel

ABSTRACT

Nanoindentation tests of the high nitrogen nickel-free austenitic stainless steel (HNS) were performed with peak load in a wide range of 100–600 mN to investigate the nanoindentation creep deformation behaviours. The results of the nanoindentation creep tests have demonstrated that the load plateaus, creep strain rate and creep stress of the cold-rolled HNS are larger and its creep stress exponent is smaller than the solution-treated HNS. The analysis reveals that the obvious creep deformation behaviour in the cold-rolled HNS arises from the rapidly relaxed dislocation structures in the initial transition regime, while the small creep deformation behaviour of the solution-treatedHNS is mainly attributed to that the stable dislocation structures for the intensive interactions between dislocations.

KEYWORDS:

• High nitrogen nickel-free austenitic stainless steel
• nanoindentation test
• nanoindentation creep deformatoin behaviour
• creep stress exponent
• solution treatment
• cold rolling
• twin
• dislocations

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by National Natural Science Foundation of China [grant number 51371089 and 51601067] and the Science and Technology Development Program of Jilin Province [grant number 20160520007JH].