Effect of laser­textured groove wall interface on molybdenum coating diffusion and metallurgical bonding

2021 ◽  
Vol 405 ◽  
pp. 126561
Author(s):  
Delong Jia ◽  
Peng Yi ◽  
Yancong Liu ◽  
Jiawei Sun ◽  
Shengbo Yue ◽  
...  
Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3700
Author(s):  
Wenquan Wang ◽  
Ming Du ◽  
Xinge Zhang ◽  
Chengqun Luan ◽  
Yingtao Tian

H13 steel is often damaged by wear, erosion, and thermal fatigue. It is one of the essential methods to improve the service life of H13 steel by preparing a coating on it. Due to the advantages of high melting point, good wear, and corrosion resistance of Mo, Mo coating was fabricated on H13 steel by electro spark deposition (ESD) process in this study. The influences of the depositing parameters (deposition power, discharge frequency, and specific deposition time) on the roughness of the coating, thickness, and properties were investigated in detail. The optimized depositing parameters were obtained by comparing roughness, thickness, and crack performance of the coating. The results show that the cross-section of the coating mainly consisted of strengthening zone and transition zone. Metallurgical bonding was formed between the coating and substrate. The Mo coating mainly consisted of Fe9.7Mo0.3, Fe-Cr, FeMo, and Fe2Mo cemented carbide phases, and an amorphous phase. The Mo coating had better microhardness, wear, and corrosion resistance than substrate, which could significantly improve the service life of the H13 steel.


Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 46
Author(s):  
Hu Xu ◽  
Junsheng Sun ◽  
Jun Jin ◽  
Jijun Song ◽  
Chi Wang

At present, most Mo2FeB2-based cermets are prepared by vacuum sintering. However, vacuum sintering is only suitable for ordinary cylinder and cuboid workpieces, and it is difficult to apply to large curved surface and large size workpieces. Therefore, in order to improve the flexibility of preparing Mo2FeB2 cermet, a flux cored wire with 70% filling rate, 304 stainless steel, 60 wt% Mo powder and 40 wt% FeB powder was prepared. Mo2FeB2 cermet was prepared by an arc cladding welding metallurgy method with flux cored wire. In this paper, the microstructure, phase evolution, hardness, wear resistance and corrosion resistance of Mo2FeB2 cermets prepared by the vacuum sintering (VM-Mo2FeB2) and arc cladding welding metallurgy method (WM-Mo2FeB2) were systematically studied. The results show that VM-Mo2FeB2 is composed of Mo2FeB2 and γ-CrFeNi.WM-Mo2FeB2 is composed of Mo2FeB2, NiCrFe, MoCrFe and Cr2B3. The volume fraction of hard phase in WM-Mo2FeB2 is lower than that of VM-Mo2FeB2, and its hardness and corrosion resistance are also slightly lower than that of VM-Mo2FeB2, but there are obvious pores in the microstructure of VM-Mo2FeB2, which affects its properties. The results show that WM-Mo2FeB2 has good diffusion and metallurgical bonding with the matrix and has no obvious pores. The microstructure is compact and the wear resistance is better than that of VM-Mo2FeB2.


Author(s):  
Hui Chen ◽  
Danai Giannopoulou ◽  
Thomas Greß ◽  
Jonas Isakovic ◽  
Tim Mittler ◽  
...  

AbstractA process chain of compound casting and co-extrusion of AA7075/6060 bilayer billets is introduced to manufacture hybrid components with strength in the core and good corrosion-resistance in the shell. Using optimized compound casting parameter, metallurgical bonding between the shell AA6060 and the core AA7075 can be achieved through remelting and recrystallization of the substrate AA7075. The locally unequal thermal conditions at the interface induces partially weak bonding. The bonding strength in greater distance from the casting gate is generally lower. Hot extrusion is applied to improve the interfacial bonding. Comparisons of the microstructure and the shear strength between as-cast billet and extrudate present the homogenization of the interfacial bonding through the process chain.


Author(s):  
M. Fang ◽  
S. Chandra ◽  
C. B. Park

Experiments were conducted to determine conditions under which good metallurgical bonding was achieved in vertical walls composed of multiple layers of droplets that were fabricated by depositing tin droplets layer by layer. Molten tin droplets (0.75 mm diameter) were deposited using a pneumatic droplet generator on an aluminum substrate. The primary parameters varied in experiments were those found to most affect bonding between droplets on different layers: droplet temperature (varied from 250°C to 325°C) and substrate temperature (varied from 100°C to 190°C). Considering the cooling rate of droplet is much faster than the deposition rate previous deposition layer cooled down too much that impinging droplets could only remelt a thin surface layer after impact. Assuming that remelting between impacting droplets and the previous deposition layer is a one-dimensional Stefan problem with phase change an analytical solution can be found and applied to predict the minimum droplet temperature and substrate temperature required for local remelting. It was experimentally confirmed that good bonding at the interface of two adjacent layers could be achieved when the experimental parameters were such that the model predicted remelting.


2017 ◽  
Vol 31 (16-19) ◽  
pp. 1744031
Author(s):  
Wenjing Chen ◽  
Hui Chen ◽  
Yongjing Wang ◽  
Congchen Li ◽  
Xiaoli Wang

The Ni–Cr–Fe metal powder was deposited on EA4T steel by laser cladding technology. The microstructure and chemical composition of the cladding layer were analyzed by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The bonding ability between the cladding layer and the matrix was measured. The results showed that the bonding between the cladding layer and the EA4T steel was metallurgical bonding. The microstructure of cladding layer was composed of planar crystals, columnar crystals and dendrite, which consisted of Cr2Ni3, [Formula: see text] phase, M[Formula: see text]C6 and Ni3B phases. When the powder feeding speed reached 4 g/min, the upper bainite occurred in the heat affected zone (HAZ). Moreover, the tensile strength of the joint increased, while the yield strength and the ductility decreased.


2018 ◽  
Vol 5 (11) ◽  
pp. 25667-25676
Author(s):  
H. Adarsha ◽  
C.S. Ramesh ◽  
Nikitha Nair ◽  
K.M. Karisiddeshwaraswamy ◽  
Anoushka Chaturvedi

2007 ◽  
Vol 280-283 ◽  
pp. 1489-1492
Author(s):  
Zhen Ting Wang ◽  
Hua Hui Chen

Micro-nanostructured WC composite coatings were successfully fabricated by induced heating sintering method on the surface of Q235 steel .The microstructure, micro-hardness and the wear resistance of the composite coatings were studied .The results show that the microstructure of induced heat layer is mainly composed of Ni-based solid solutions and WC particles. And there exists excellent metallurgical bonding between coating and substrate. The wear resistance of micro-nanostructured WC Composite Coatings is increased by 1.5 times on an average as compared with that of micron.


2011 ◽  
Vol 704-705 ◽  
pp. 1112-1116
Author(s):  
Yu Liang Liu ◽  
Tian Ying Xiong ◽  
Jie Wu

Cold Gas Dynamic Spraying (CGDS) has been developed to fabricate surface coating as a new technique in recent years. In this paper, aluminum bronze particles were sprayed on 45 steel and 316L stainless steel by CGDS, and the coating was sucessfully fabricated on the surface of the steels. The microstructure of the coating and the interface between the coating and the substrate were investigated by scanning electron microscope (SEM), energy dispersive (EDX) and XRD. It was found that the coating was dense and its porosity was low, while the microhardness of the coating was lower than that of the bulk one; Mechanical bonding was the main formation mechanism of the coating, and there was metallurgical bonding too; Diffusion occured at the interface between the coating and substrate; α phase in aluminum bronze particles transformed to β phase after the spray and the transformation was induced by the plastic strain during spraying.


2012 ◽  
Vol 590 ◽  
pp. 51-55
Author(s):  
Hui Yang ◽  
Guo Dong Zhang ◽  
Yuan Mei Fei

With the self-designed welding powder formula,this experiment employed the SHS reaction to weld the base metal,which was steel Q235 here,then respectively used Olympus large-scale horizontal digital microscope to analyze the structure morphology of the welding seam's different regions,JEOL SEM to point-analyze and line-analyze elements' distribution near the the weld interface and HV-1000 CCD automatic measurement microscopic vickers hardness tester to measure the microhardness of the pure copper's welding seam.The experiment's result shows the hardness of different part of the welded joint varies largely,and that the join of alloy elements can increase the microhardness of the welding metal,and that the welding metal and base metal interdiffuse,grow and mix remarkably near the fusion line,realizing wonderful metallurgical bonding.


Sign in / Sign up

Export Citation Format

Share Document