Influences of Laser Surface Alloying with Cr on Microstructural Characteristics and Hardness of Pure Ti

  • PDF / 2,989,282 Bytes
  • 11 Pages / 593.972 x 792 pts Page_size
  • 39 Downloads / 213 Views

DOWNLOAD

REPORT


TITANIUM (Ti) and its alloys are extensively used in aerospace, chemical, and biomedical industries owing to high specific strength, excellent corrosion resistance, and biocompatibility.[1–4] However, under severe friction conditions, surface wear failure often occurs rapidly due to their relatively poor tribological properties and hardness that lead to limited utilization.[5] In order to TINGTING WANG and TIJUAN CHENG are with the College of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054, P.R. China. LINGGUO ZENG and ZHIJUN LI are with the Chongqing Yufeng Wire and Cable Co., Ltd, Chongqing 402260, P.R. China. LINJIANG CHAI is with the College of Materials Science and Engineering, Chongqing University of Technology and also with the Department of Mechanical and Materials Engineering, Queen’s University, Kingston, ON K7L3N6, Canada. Contact e-mail: [email protected] LING ZHANG is with the College of Materials Science and Engineering, Chongqing University, Chongqing 400044, P.R. China. Contact e-mail: [email protected] Manuscript submitted December 18, 2018. Article published online June 3, 2019 3794—VOLUME 50A, AUGUST 2019

attain optimized surface performance, many researchers have conducted various surface modification attempts.[6–10] Among them, laser surface treatments attract a lot of attentions due to its advantages like high efficiency, convenient processing, and remarkable modification effects. For example, Chen et al.[11] reported that resistance to abrasive wear of Ti-6Al-4V alloy would be effectively enhanced by pulsed laser processing because of the formation of hard martensitic phases in the surface layer. Fogagnolo et al.[9] found that a favorable combination of wear and fatigue resistance could be reached for commercially pure Ti surfaces after controlled laser surface alloying (LSA) with Nb, which was able to markedly increase hardness with slightly reduced Young’s modulus. Owing to beneficial effects on improving hardness and corrosion resistance, Cr is often used as a major alloying element in Fe, Al, and Ti base materials for optimizing their properties of either bulk or surface or both.[12,13] For Ti, Cr is a b-stabilizing element and can form intermetallic compounds with Ti through a eutectoid reaction.[14] In recent work, Wei et al.[15] conducted

METALLURGICAL AND MATERIALS TRANSACTIONS A

double-glow plasma surface chromising on Ti-6Al-4V alloy and found that the formed modification layer possessed higher oxidation resistance. By employing a laser powder deposition technique, Zhang et al.[16] prepared Ti-Cr alloys with the content of Cr gradiently changed from the surface to the bulk and found that the presence of both metastable b-Ti and TiCr2 phases near the surface led to significantly increased hardness. A study by Hsu et al.[17] on binary Ti-Cr alloys with different Cr contents revealed that the alloys with more Cr additions were always harder, suggesting a strong solid solution hardening effect of Cr on Ti. One may reasonably expect the surfac

Data Loading...