Abstract
The application of components often depends to a large extent on the properties of the surface layer. A novel process chain for the production of components with a hardened surface layer from metastable austenitic steel was presented. The investigated metastable austenitic AISI 347 steel was cold-drawn in solution annealed condition at cryogenic temperatures for pre-hardening, followed by post-hardening via cryogenic turning. The increase in hardness in both processes was due to strain hardening and deformation-induced phase transformation from γ-austenite to α′-martensite. Cryogenic turning experiments were carried out with solution annealed AISI 347 steel as well as with solution annealed and subsequently cold-drawn AISI 347 steel. The thermomechanical load of the workpiece surface layer during the turning process as well as the resulting surface morphology was characterized. The forces and temperatures were higher in turning the cold-drawn AISI 347 steel than turning the solution annealed AISI 347 steel. After cryogenic turning of the solution annealed material, deformation-induced phase transformation and a significant increase in hardness were detected in the near-surface layer. In contrast, no additional phase transformation was observed after cryogenic turning of the cold-drawn AISI 347 steel. The maximum hardness in the surface layer was similar, whereas the hardness in the core of the cold-drawn AISI 347 steel was higher compared to that in the solution annealed AISI 347 steel.
Highlights
The first austenitic Cr–Ni steel was developed by Maurer and Strauss at the Friedrich Krupp AG and patented in 1912 [1]
A subsequent process for surface layer hardening is often necessary, since the application behavior of a component is decisively determined by the properties of its Combination of cold drawing and cryogenic turning for modifying surface morphology of
This paper presents a newly developed process chain for the manufacture of hardened components from metastable austenitic steel
Summary
The first austenitic Cr–Ni steel was developed by Maurer and Strauss at the Friedrich Krupp AG and patented in 1912 [1]. Based on the chemical composition of the ‘‘Versuchsschmelze 2 Austenit’’ (V2A) developed at that time, numerous nuances of this metastable austenitic steel exist today. Due to their good mechanical properties and their high corrosion resistance in particular, metastable austenitic steels are widely used in the chemical. The conventional process chain in the manufacture of metastable austenitic steel components usually begins with the casting of the melt in a continuous casting process. Metastable austenitic steels are characterized by a relatively low hardness in the solution annealed condition. A subsequent process for surface layer hardening is often necessary, since the application behavior of a component is decisively determined by the properties of its Combination of cold drawing and cryogenic turning for modifying surface morphology of
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
