Microstructural, thermal and mechanical properties of HVOF sprayed Ni–Al-based bond coatings on stainless steel substrate

AbstractEffects of heat treatment on the mechanical properties of Ni films on 430 stainless steel substrate were investigated. The Ni films were annealed at heat treatment temperatures ranging from 0 °C to 800 °C for 2 h. The surface morphology, composition, and texture orientation of Ni films were studied by scanning electron microscopy, energy dispersive spectrometry, and X-ray diffraction. The load–indentation depth curves of Ni films before and after heat treatment were measured by using nanoindentation method. In conjunction with finite element modeling and dimensional analysis, the stress–strain relationships of Ni films on 430 stainless steel substrate at different temperatures are successfully obtained by using a power-law hardening model.

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Heat Input Effect on Microstructure and Mechanical Properties of Electron Beam Additive Manufactured (EBAM) Cu-7.5wt.%Al Bronze

Materials ◽

10.3390/ma14226948 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6948

Author(s):

Andrey Filippov ◽

Nikolay Shamarin ◽

Evgeny Moskvichev ◽

Nikolai Savchenko ◽

Evgeny Kolubaev ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Stainless Steel ◽

Electron Beam ◽

Heat Input ◽

Stainless Steel Substrate ◽

Tensile Axis ◽

Steel Substrate ◽

Equiaxed Grains ◽

Wire Feed

Electron beam additive wire-feed deposition of Cu-7.5wt.%Al bronze on a stainless-steel substrate has been carried out at heat input levels 0.21, 0.255, and 0.3 kJ/mm. The microstructures formed at 0.21 kJ/mm were characterized by the presence of both zigzagged columnar and small equiaxed grains with 10% of Σ3 annealing twin grain boundaries. No equiaxed grains were found in samples obtained at 0.255 and 0.3 kJ/mm. The zigzagged columnar ones were only retained in samples obtained at 0.255 kJ/mm. The fraction of Σ3 boundaries reduced at higher heat input values to 7 and 4%, respectively. The maximum tensile strength was achieved on samples obtained with 0.21 kJ/mm as tested with a tensile axis perpendicular to the deposited wall’s height. More than 100% elongation-to-fracture was achieved when testing the samples obtained at 0.3 kJ/mm (as tested with a tensile axis coinciding with the wall’s height).

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Stress corrosion and mechanical properties of zinc coating on 304 stainless steel

Materials Testing ◽

10.1515/mt-2020-0035 ◽

2021 ◽

Vol 63 (3) ◽

pp. 209-218

Author(s):

Hua Zhang ◽

Sihan Zheng ◽

Yue Wang ◽

QiLiang Li ◽

Jie Tao ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Stainless Steel ◽

Stress Corrosion ◽

Stainless Steel Substrate ◽

Steel Substrate ◽

Zinc Coating ◽

304 Stainless Steel ◽

Three Point Bending ◽

Indentation Tests

Abstract The effect of stress corrosion on the mechanical properties of the coating in the zinc coating/304 stainless steel substrate system was investigated by three-point bending, slow strain rate tensile (SSRT) and nano-indentation tests. Studies have shown that fracture toughness was improved when the coating was thick but weakened when the coating was thin. At varied coating thicknesses (80 μm, 160 μm, 240 μm, 320 μm, 400 μm), the decline rates of the fracture toughness were 77.48 %, 71.82 %, 66.67 %, 55.48 % and 51.52 %, respectively, and those for the critical strain of crack initiation were 94.97 %, 91.88 %, 88.42 %, 76.19 % and 74.33 %, respectively. In addition, simulations were made to analyze the crack propagation of zinc coating in coating/substrate system under tensile loading by ABAQUS, which proved the accuracy of the experiment.

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Influence of Bond Material Concentration on the Mechanical Properties of Fixed Abrasive Lapping Tool for Stainless Steel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.499.372 ◽

2012 ◽

Vol 499 ◽

pp. 372-377

Author(s):

C.R. Zhu ◽

B.H. Lv ◽

Ju Long Yuan

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Shear Strength ◽

Modulus Of Elasticity ◽

Stainless Steel Substrate ◽

Steel Substrate ◽

Abrasive Tool ◽

Micro Structure ◽

Sem Images ◽

Fixed Abrasive

To improve the machining efficiency as well as surface roughness, a resin-bonded fixed abrasive tool is developed for lapping process of stainless steel substrate. To optimize the lapping ability of the fixed abrasive tool, the influences of bond material concentration on the mechanical properties of fixed abrasive lapping tool, including structure hardness, shear strength, the water-absorbing capacity and modulus of elasticity in compression are investigated. The micro structure of tools is also observed. Tools made of #1000 SiC abrasive and resin with different concentrations is employed in the tests. It is found, the hardness, shear strength, and modulus of elasticity in compression reach highest value, as the 35%wt bond material are used. The water-absorbing capacity increases as the bond material concentration decreases. It is judged from the SEM images that the number of pores in tool with 35%wt bond material is at the most.

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