Influence of Process Parameters on Microstructure of Reaction Plasma Cladding TiC-Fe-Cr Coating

2021 ◽  
Vol 1027 ◽  
pp. 170-176
Author(s):  
Li Mei Wang ◽  
Jun Bo Liu ◽  
Jun Hai Liu
Keyword(s):  
Process Parameters ◽  
Composite Powder ◽  
Early Stage ◽  
Influence Of Process Parameters ◽  
Synthetic Process ◽  
Plasma Cladding ◽  
Cr Coating ◽  
Composition Process ◽  
Cladding Layers

In order to improve the quality and properties of the coating, a certain amount of Ti was added to the plasma cladding Fe-Cr-C coating in the early stage. And Fe-Cr-C-Ti composite powder was prepared by precursor carbonization-composition process. In situ synthesized TiC-Fe-Cr coatings were fabricated on substrate of Q235 steel by plasma cladding process with Fe-Cr-C-Ti composite powder. Microstructure of the coating with different process parameters, including cladding current, cladding speed, number of overlapping cladding layers, were analyzed by scanning electron microscope (SEM). The results show that the structure of the TiC-Fe-Cr coating is greatly affected by the fusion current, the cladding speed and the overlapping cladding process. In this test, when the cladding current of 300A and the cladding process parameter of the cladding speed of 50 mm/min are clad with three layers, a well-formed and well-structured TiC-Fe-Cr coating can be obtained. Which are the best synthetic process parameters in this test.

Cracking Behavior of Two Kinds of Plasma Cladding Layers by Precursor Carbonization-Composition Process

2013 ◽  
Vol 690-693 ◽  
pp. 2046-2050
Author(s):  
Jun Bo Liu
Keyword(s):  
Composite Powder ◽  
Raw Materials ◽  
Base Material ◽  
Fiber Direction ◽  
X Ray Diffraction ◽  
Cracking Behavior ◽  
Plasma Cladding ◽  
Reactive Plasma ◽  
Composition Process ◽  
Cladding Layers

In-situ synthesized two kinds of Fe-Cr-C and Fe-Cr-C-Ti layers were fabricated on the base of Q235 steel by reactive plasma cladding process using composite powder prepared by precursor carbonization-composition process as raw materials. The composite powder is composed of ferrotitanium, chromium, iron and precursor sucrose. Microstructure of the layer was observed by scanning electron microscope (SEM). The phases in the layer were determined by X-ray diffraction (XRD). Results indicate that the Fe-Cr-C layer consists of primary (Cr,Fe)7C3 carbide, chrysanthemum-shaped eutectic (Cr,Fe)7C3 carbide and eutectic austenite. The cracks in Fe-Cr-C layer might originate at the interface of the layer and the base material as well as at the pores or edges of the layer. These cracks expand along primary (Cr,Fe)7C3 grain boundaries in a crystalline form. Because the grains of primary (Cr,Fe)7C3 are fiber-shaped and the fiber direction are perpendicular to the surface of the layer, so the cracks expand perpendicularly throughout of the Fe-Cr-C layer. The Ti addition into Fe-Cr-C plays an important role in synthesizing TiC and austenite, reducing primary (Cr,Fe)7C3 and improving the microstructure of eutectic (Cr,Fe)7C3. Therefore, Fe-Cr-C-Ti has good performance in toughness and crack-resistance.

TiC Particle Reinforced Reactive Plasma Cladding Composite Coating by the Precursor Carbonization-Composition Process

2011 ◽  
Vol 291-294 ◽  
pp. 167-171
Author(s):  
Jun Bo Liu ◽  
Li Mei Wang ◽  
Jun Sheng Jiang ◽  
Guang Ming Cao
Keyword(s):  
Composite Coating ◽  
Fusion Zone ◽  
Composite Powder ◽  
Base Material ◽  
Q235 Steel ◽  
Plasma Cladding ◽  
Reactive Plasma ◽  
Tic Particle ◽  
Composition Process

Fe-Cr-Ti-C composite powder was prepared by precursor carbonization-composition process using the mixture of ferrotitanium, chromium, iron powders and precursor sucrose as raw materials. In situ synthesized TiC particle reinforced composite coating was fabricated on substrate of Q235 steel by reactive plasma cladding process using Fe-Cr-Ti-C composite powder. Microstructure of the coating was observed by scanning electron microscope (SEM), the phases in the coating were determined by X-ray diffraction (XRD), and the wear resistance of the composite coating was evaluated under dry sliding wear test conditions at room temperature. Results indicate that the composite coating consists of in-situ the reinforcing TiC carbide, (Cr,Fe)7C3 eutectics and austenitic, and is metallurgically bonded to the Q235 steel substrate. TiC carbide in the composite coating showed the gradient distribution. TiC particles present granular in the fusion zone and central zone, and present dendritic in the surface of the composite coating. Hardness of the coating from surface to fusion zone is little difference, the average hardness of the coating is about HV0.2750, is as 3.2 times as the base. The wear mass loss of Q235 base material is 12 times as that of the composite coating.

scholarly journals Processing-structure-property correlations of in situ Al/TiB2 composites processed by aluminothermic reduction process

2018 ◽  
Vol 25 (5) ◽  
pp. 869-879
Author(s):  
A.S. Vivekananda ◽  
S. Balasivanandha Prabu ◽  
R. Paskaramoorthy
Keyword(s):  
Process Parameters ◽  
Particle Distribution ◽  
Reduction Process ◽  
Xrd Analysis ◽  
Parent Material ◽  
Structure Property ◽  
Influence Of Process Parameters ◽  
Average Hardness ◽  
Al Matrix

AbstractThis paper reports the influence of process parameters on the size and distribution of in situ titanium diboride (TiB2) particles within the aluminium (Al) matrix. TiB2 particles were formed as a result of the in situ reaction of potassium hexafluorotitanate (K2TiF6) and potassium tetra fluoroborate (KBF4) with molten Al. Two process parameters, namely, the addition time (AT) and holding time (HT) of precursor salts, were considered. The Al/TiB2 composites were produced by allowing the in situ reaction to occur at various ATs (10, 20, and 30 min) and HTs (20, 30, and 40 min). Results showed that the formation of TiB2 was confirmed by XRD analysis. The microstructure, TiB2 particle size, hardness, yield strength (YS), and ultimate tensile strength (UTS) were strongly affected by the said process parameters. The variations in hardness and UTS were highly consistent with those found in the microstructure of the composites. Compared with the Al parent material, the increase in the average hardness and UTS of the composite were 51% and 44%, respectively. This improvement was achieved for the composite sample fabricated with 20 min of AT and 30 min of HT. At this condition, the composite displayed near-uniform particle distribution.

scholarly journals Three-point bending study on the microscopic fracture behavior of pre-oxidized Cr-coated Zr-4 alloys

2021 ◽  
Vol 2076 (1) ◽  
pp. 012051
Author(s):  
Mingyue Du ◽  
Chenxue Wang ◽  
Jishen Jiang ◽  
Xianfeng Ma
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Fracture Behavior ◽  
Early Stage ◽  
Bending Test ◽  
Cracking Behavior ◽  
Three Point Bending ◽  
Crack Penetration ◽  
Cr Coating

Abstract In this study, an in situ three-point bending test was carried out to study the mechanical properties and cracking behavior of the Cr-coated Zr-4 alloy considering the effect of pre-oxidation. The results showed that high temperature pre-oxidation led to the formation of intermetallic ZrCr2 at the coating/substrate interface and an α-Zr(O) layer beneath the interface. During the three-point bending test, the Cr coating and Zr-4 substrate showed good plastic deformation. However, the brittle intermetallic ZrCr2 diffusion layer exhibited cracks in the early stage, which accelerated the crack penetration to the Cr coating and the Zr-4 substrate, leading to the pre-failure of the pre-oxidized sample.

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