The Effect of Flood, High-Pressure Cooling, and CO2-Assisted Cryogenic Machining on Microhardness, Microstructure, and X-ray Diffraction Patterns of NiTi Shape Memory Alloy

Kitay O., Kaynak Y.

JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE, cilt.30, ss.5799-5810, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 30
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1007/s11665-021-05854-6
  • Dergi Adı: JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), Chemical Abstracts Core, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.5799-5810
  • Anahtar Kelimeler: CO2, cryogenic machining, crystallite size, high-pressure cooling (HPC), NiTi shape memory alloy, surface integrity, XRD analysis, SURFACE INTEGRITY, TRANSFORMATION BEHAVIOR, MEDICAL APPLICATIONS, TOOL-WEAR, PERFORMANCE, PHASE, DRY, MACHINABILITY, MQL
  • Marmara Üniversitesi Adresli: Hayır

Özet

This study focuses on the effects of various cutting speeds and cutting conditions including dry, CO2, HPC and flood on the surface integrity characteristics of the machined NiTi alloy. Machining-induced affected layer, microstructure, microhardness and XRD analysis are considered to assess the surface integrity characteristics of NiTi alloy. The findings from this current study reveal that as the cutting speed increased, the depth of the machining-induced layer decreased. While the microhardness value of the machined samples increased in all of the cutting conditions compared to the as-received hardness, the greatest increase was in the CO2 condition, with 36%. The highest peak intensities of the B2 main austenite XRD peaks occurred at the cutting speed of 70 m/min. The full width at half maximum values of the XRD peaks increased in all of the cutting conditions, especially at the cutting speed of 20 m/min, and this situation supports the microhardness increase. The smallest crystallite size occurred under the CO2 condition at the cutting speed of 20 m/min, while the highest dislocation density occurred under the HPC condition at the same cutting speed.