Diametral compression test method to analyse relative surface stresses in thermally sprayed coated and uncoated circular disc specimens

SURFACE & COATINGS TECHNOLOGY

卷:357

Article

Faisal, N. H.¹  Mann, L.¹  Duncan, C.¹  Dunbar, E.¹  Clayton, M.¹  Frost, M.¹  McConnachie, J.¹  Fardan, A.²  Ahmed, R.² 

[1] Robert Gordon Univ, Sch Engn, Garthdee Rd, Aberdeen AB10 7GJ, Scotland

[2] Heriot Watt Univ, Sch Engn & Phys Sci, Edinburgh EH14 4AS, Midlothian, Scotland

关键词: Diametral compression test;    Brazilian test;    Thermal spray coatings;    Strain gauge, residual stress;    Analytical method;    Finite element;   

DOI  :  10.1016/j.surfcoat.2018.10.053

来源: Elsevier

【 摘 要 】

In firsts of its investigation, a diametral compression destructive testing method (also known as Brazilian test) was performed on thermally sprayed coated and uncoated circular disc specimens to compare relative surface stresses. The coating investigated had about 250 mu m thickness deposited on 4.76 mm thick Hastelloye (R) X substrate discs of 20 mm diameter. In the instrumented experiment (diametral compression test) strain gauge rosettes were used to measure strains on two circular surfaces of disc specimen (coated and uncoated sides) and converted to stress values for analysis. Where comparisons were made, the experimental and finite element simulation results were in some agreement with overall understanding of the diametral compression testing behaviour. For coated specimen, test results convey that higher stresses exist within the uncoated side of the specimen rather than the coated side. Although the methods proposed would be deemed most comparable to real life scenarios (e.g. to quantify coating delamination strength and failure mechanics), this type of experimental investigation has certain advantages and limitations.

【 授权许可】

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