Microstructure and Abrasive Wear Studies of Laser Clad Al-Si/SiC Composite Coatings

2007 ◽  
Vol 537-538 ◽  
pp. 89-95
Author(s):  
R. Anandkumar ◽  
Rogerio Colaço ◽  
Václav Ocelík ◽  
Jeff T.M. de Hosson ◽  
Rui Vilar
Keyword(s):  
Wear Rate ◽  
Abrasive Wear ◽  
Specific Energy ◽  
Composite Coatings ◽  
Average Diameter ◽  
Processing Parameters ◽  
Injection Velocity ◽  
Particle Injection ◽  
Average Hardness ◽  
Sic Particles

Surface coatings of Al-Si/SiC metal-matrix composites were deposited on Al-7 wt. % Si alloy substrates by laser cladding. The microstructure of the coatings was characterized by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The microstructure of the coating material is profoundly influenced by the processing parameters used, in particular by the particle injection velocity and by the specific energy. When the injection velocity is low or specific energy is high excessive dissolution of SiC in the melt pool occurs. The microstructure of the coatings presents partially dissolved SiC particles, and considerable proportions of Al4SiC4 plates and faceted Si equiaxed crystals dispersed in a α-Al+Si eutectic matrix. On the contrary for high injection velocity or low specific energy dissolution of SiC is very limited and the microstructure of the coatings consists essentially of undissolved SiC particles in a matrix consisting of primary α-Al dendrites and α-Al+Si eutectic. Abrasive wear tests were performed on the coatings using a ball cratering device and a 35 wt. % suspension of 4.25 μm average diameter SiC particles in water as abrasive. Coatings prepared with a high specific energy present an average hardness of 248 HV and an average abrasive wear rate of 17.4x10-5 mm3/m. Coatings deposited with a low specific energy exhibit an average hardness of 117 HV and an average abrasive wear rate of 4.3 x10-5 mm3/m.

scholarly journals Optimization of milling process parameters and prediction of abrasive wear rate increment based on cutting force experiment

2021 ◽  
Vol 13 (8) ◽  
pp. 168781402110399
Author(s):  
Fei Li ◽  
Jun Liu
Keyword(s):  
Wear Rate ◽  
Abrasive Wear ◽  
Cutting Force ◽  
Process Parameters ◽  
Processing Time ◽  
Production Efficiency ◽  
Processing Parameters ◽  
Numerical Control ◽  
Cnc Milling ◽  
Milling Cutter

Tuning the parameters of Computerized Numerical Control (CNC) is essential for practical manufacturers. Well configured parameters ensure the efficiency of production and the accuracy of the products. However, with the abrasive wear on the flank of the milling cutter, the milling processing parameters should re-configure to adapt to the increment of the abrasive wear. This paper aims to propose a method to predict the abrasive wear rate increment on the flank of the milling cutter and optimize the processing parameters of CNC milling. Firstly, we set a cutting data acquisition system to sample the processing time and cutting force among X, Y coordinates based on the five-factor and four-level orthogonal experiments. Then, the sampled cutting force data increment is transformed into the abrasive wear rate increment by applying the incremental model. Next, five processing parameters for CNC milling are optimized by the gray relational method, which takes the limited abrasive wear rate increment of the flank face and the non-increasing processing time as the constrained conditions. We obtain the relationship between five processing parameters and abrasive wear rate increment. We also find the basic principle of selecting process parameters is to reduce the abrasive wear rate without increasing the processing time. The experimental results verify that the optimized process parameters make the gray relational degree increase by 0.02, and the abrasive wear rate increment decreases by 0.42432 × 10−10 mm3/s without affecting the production efficiency. In the prediction section, by applying the Back Propagation (BP) neural network, we obtain an accurate prediction model from measurable five factors to the abrasive wear increment on the flank of the milling cutter. The maximum error between the predicted value and the actual value is 0.0003, and the predicted value curve fits well with the actual value curve. From the perspective of abrasive wear rate increment prediction, it provides a new idea for online tool wear monitoring.

Tribological Properties of Ni-Base Alloy Coatings Reinforced by SiC Particles

2012 ◽  
Vol 538-541 ◽  
pp. 181-185
Author(s):  
Ting Xu ◽  
Ye Fa Tan ◽  
Bin Liu
Keyword(s):  
Plastic Deformation ◽  
Wear Resistance ◽  
Carbon Steel ◽  
Wear Rate ◽  
Tribological Properties ◽  
Adhesive Wear ◽  
Base Alloy ◽  
Composite Coatings ◽  
Alloy Coating ◽  
Sic Particles

Ni-Co/SiC composite coatings embedded with different sizes of micron-Sic particles were prepared on the surfure of 45 carbon steel through electrochemical deposition. The effects of size of SiC particles on the microstructure, the hardness and tribological properties of the composite coatings were investigated. The results show that the decrease of the size may increase the hardness, make microstructure closer and greatly improve their wear resistance. The Ni-Co/SiC(W7) coating exhibit better integrated properties, its hardness was HV505, 20 percent higher than Ni-Co alloy coating, and its wear rate was only 1/5 of the Ni-Co/SiC(W40) coating. The wear mechanisms of the coatings are mainly plastic deformation with slight adhesive wear.

Increasing in wear resistance of excavating machine elements

2020 ◽  
pp. 306-308
Author(s):  
V.S. Bochkov
Keyword(s):  
Wear Resistance ◽  
Wear Rate ◽  
Abrasive Wear ◽  
Thermomechanical Treatment ◽  
Cold Work ◽  
Hadfield Steel ◽  
Outer Side ◽  
Viii And Ix ◽  
Machine Elements ◽  
The Impact

The relevance of the search for solutions to increase the wear resistance of bucket teeth of excavating machine type front shovel is analyzed. The reasons for the wear of the teeth are considered. It is determined that when excavating machines work for rocks of VIII and IX categories, impact-abrasive wear of the inner side of the teeth and abrasive external wear occurs. It is proved that the cold-work hardening of Hadfield steel (the teeth material), which occurs during the excavating machine teeth work in the rocks of VIII and IX categories, reduces the impact-abrasive wear rate on the inner side of the teeth and does not affect the abrasive wear of the outer. The methods for thermomechanical treatment of the outer side of the excavating machine tooth is proposed. It can increase the wear resistance of Hadfield steel (110G13L) up to 1.7 times and lead to the self-sharpening effect of the tooth due to equalization of the wear rate of the outer and inner parts of the tooth. The efficiency factor of thermomechanical treatment to reduce the of abrasive wear rate of Hadfield steel is experimentally proved.

scholarly journals The Effect of Co-Deposition of SiC Sub-Micron Particles and Heat Treatment on Wear Behaviour of Ni–P Coatings

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 180
Author(s):  
Donya Ahmadkhaniha ◽  
Lucia Lattanzi ◽  
Fabio Bonora ◽  
Annalisa Fortini ◽  
Mattia Merlin ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Friction Coefficient ◽  
Wear Mechanisms ◽  
Composite Coatings ◽  
Wear Behaviour ◽  
Maximum Hardness ◽  
Sic Particles ◽  
Heat Treated ◽  
The Coefficient Of Friction ◽  
The Difference

The purpose of the study is to assess the influence of SiC particles and heat treatment on the wear behaviour of Ni–P coatings when in contact with a 100Cr6 steel. Addition of reinforcing particles and heat treatment are two common methods to increase Ni–P hardness. Ball-on-disc wear tests coupled with SEM investigations were used to compare as-plated and heat-treated coatings, both pure and composite ones, and to evaluate the wear mechanisms. In the as-plated coatings, the presence of SiC particles determined higher friction coefficient and wear rate than the pure Ni–P coatings, despite the limited increase in hardness, of about 15%. The effect of SiC particles was shown in combination with heat treatment. The maximum hardness in pure Ni–P coating was achieved by heating at 400 °C for 1 h while for composite coatings heating for 2 h at 360 °C was sufficient to obtain the maximum hardness. The difference between the friction coefficient of composite and pure coatings was disclosed by heating at 300 °C for 2 h. In other cases, the coefficient of friction (COF) stabilised at similar values. The wear mechanisms involved were mainly abrasion and tribo-oxidation, with the formation of lubricant Fe oxides produced at the counterpart.

Machining and Wear of High-Alumina Ceramics for Structural Applications

2009 ◽  
Vol 409 ◽  
pp. 137-144 ◽  
Author(s):  
Stojana Veskovic-Bukudur ◽  
Tanja Leban ◽  
Milan Ambrozic ◽  
Tomaž Kosmač
Keyword(s):  
Grain Size ◽  
Wear Rate ◽  
Abrasive Wear ◽  
Direct Relationship ◽  
Bending Strength ◽  
High Alumina ◽  
Alumina Ceramics ◽  
Large Area ◽  
Structural Applications ◽  
Worn Surfaces

The wear resistances of four standard-grade high-alumina ceramics were evaluated and related to their machining ability. Three of the material grades contained 96% of alumina and 4% of either calcium silicate, or magnesium silicate, or manganese titanate in the starting-powder composition. The nominal alumina content in the fourth material was 99.7%. The specimens were fabricated using a low-pressure injection-molding forming technique, followed by thermal de-binding and sintering. After sintering the four materials differ significantly in their grain size, bending strength and Vickers hardness. No direct relationship between the microstructural parameters and the mechanical properties was found, but there was a grain-size dependence of the surface finish after grinding under industrial conditions. The two silicate-containing ceramics exhibited considerably higher wear resistances than the two silicate-free ceramics, but no direct relationship between the abrasive wear rate during grinding and the cutting time was observed. The cutting ability represents a valuable material characteristic for industrial practice, but it should not be directly used for predicting the wear rate during grinding. Quantitative differences in the cutting time and abrasive wear rate were manifested in the different topographies of the worn surfaces. Cutting resulted in relatively large area fractions of plastically deformed surfaces, whereas pullouts dominated the worn surfaces after grinding.

A STUDY OF COMPOSITE COATINGS ON 22MnCrNiMo STEEL FOR MOORING CHAIN

2018 ◽  
Vol 25 (03) ◽  
pp. 1850074
Author(s):  
YAN SHEN ◽  
PRASANTA K. SAHOO ◽  
YIPENG PAN
Keyword(s):  
Corrosion Resistance ◽  
Experimental Work ◽  
Structural Characteristics ◽  
Composite Coatings ◽  
Salt Spray ◽  
Corrosion Performance ◽  
Sic Particles ◽  
Pulsed Electrodeposition ◽  
Mooring Chain ◽  
Spray Treatment

In order to enhance the corrosion resistance of mooring chain, the composite coatings are carried out on the surface of 22MnCrNiMo steel for mooring chain by double-pulsed electrodeposition technology using centrifugal force in the rotating device. The microstructure and anti-corrosion performance of the composite coatings have been investigated experimentally. This paper mainly focuses on the experimental work to determine the structural characteristics and corrosion resistance of composite coatings in the presence of nano-SiC. The results show that the presence of nano-SiC has a significant effect on the preparation of composite coating during the process. The surface of the coating becomes compact and smooth at a moderate concentration of nano-SiC particles. Furthermore, the best corrosion resistance of the composite coatings can be obtained when the concentration of nano-SiC particles is 2.0[Formula: see text]g.L[Formula: see text] after salt spray treatment.

scholarly journals Enhanced Mechanical and Tribological Capabilities of a Silicon Aluminum Alloy with an Electroplated Ni–Co–P/Si3N4 Composite Coating

Metals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 120
Author(s):  
Zhijie Li ◽  
Fei Ma ◽  
Dongshan Li ◽  
Shanhong Wan ◽  
Gewen Yi ◽  
...  
Keyword(s):  
Abrasive Wear ◽  
Composite Coating ◽  
Composite Coatings ◽  
Engine Oil ◽  
Si Substrate ◽  
Wear Performance ◽  
Cobalt Layer ◽  
Hard Chrome ◽  
Electroplating Process ◽  
Hardness Values

Ni–Co–P/Si3N4 composite coatings were fabricated over an aluminum–silicon (Al–Si) substrate using a pulse-current electroplating process, in which the rapid deposition of an intermediate nickel–cobalt layer was used to improve coating adhesion. The microstructure, mechanical, and tribological behaviors of the electroplated Ni–Co–P/Si3N4 composite coating were characterized and evaluated. The results revealed that the electroplated Ni–Co–P/Si3N4 composite coating primarily consisted of highly crystalline Ni–Co sosoloid and P, and a volumetric concentration of 7.65% Si3N4. The electroplated Ni–Co–P/Si3N4 composite coating exhibited hardness values almost two times higher than the uncoated Al–Si substrate, which was comparable to hard chrome coatings. Under lubricated and dry sliding conditions, the electroplated Ni–Co–P/Si3N4 composite coating showed excellent anti-wear performance. Whether dry or lubricated with PAO and engine oil, the composite coating showed minimum abrasive wear compared to the severe adhesive wear and abrasive wear observed in the Al–Si substrate.

scholarly journals DIC TEXTURING-ASSISTED ACCELERATED SOLVENT EXTRACTION OF ACTIVE MOLECULES OF POMEGRANATE PEEL

2016 ◽  
Vol 12 (9) ◽  
pp. 4023-4044
Author(s):  
Karim Allaf ◽  
Khaoula Elaydi ◽  
Ibtisam Kamal ◽  
Ahmed Bedoui
Keyword(s):  
Solvent Extraction ◽  
Radical Scavenging ◽  
Effective Diffusivity ◽  
Bioactive Compound ◽  
Average Diameter ◽  
Processing Parameters ◽  
Accelerated Solvent Extraction ◽  
Raw Material ◽  
Phenol Compounds ◽  
Instant Controlled Pressure Drop

The current work discusses the use of Instant Controlled Pressure Drop (DIC) as a pretreatment texturing stage intensifying phenolic compound extraction from South Tunisian Punicagranatum L. peels in both cases of conventional and Accelerated Solvent Extraction (ASE). Response Surface Methodology (RSM) allowed identifying the effects of DIC processing parameters on the yields of Total Phenol Compounds (TPC), Total Flavonoid (TF), Condensed Tannins (CT), and Hydrolysable Tannins (HT), and antioxidant capacities via 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity and ß-carotene-linoleic acid as responses. Comparative methods were used to evaluate DIC-textured and Raw samples. The results obtained confirmed that appropriate DIC-texturing improved both kinetic and yield of bioactive compound extraction using ASE from Punicagranatum L. peels. Extraction kinetics was studied through Coupled Washing-Diffusion CWD model. The effective diffusivity was identified and quantified ranged from 0.27 to 8.22 against 0.4710-10 m2s-1 for DIC textured and raw material (RM), respectively. DIC swelling enabled solid vegetal material matrix to expand and be more adapted to mass transfer thus increasing extractability of the phenol compounds. Scanning Electron Microscope SEM showed that DIC generated pores with an average diameter of 50 µm.

scholarly journals Influence of load and reinforcement content on selected tribological properties of Al/SiC/Gr hybrid composites

2018 ◽  
Vol 18 (18) ◽  
pp. 18-23 ◽  
Author(s):  
Sandra Veličković ◽  
Slavica Miladinović ◽  
Blaža Stojanović ◽  
Ružica R. Nikolić ◽  
Branislav Hadzima ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Friction Coefficient ◽  
Wear Rate ◽  
Tribological Properties ◽  
Metal Matrix ◽  
Hybrid Composites ◽  
Tribological Characteristics ◽  
Volume Fractions ◽  
Sic Particles ◽  
The Matrix

Abstract Hybrid materials with the metal matrix are important engineering materials due to their outstanding mechanical and tribological properties. Here are presented selected tribological properties of the hybrid composites with the matrix made of aluminum alloy and reinforced by the silicon carbide and graphite particles. The tribological characteristics of such materials are superior to characteristics of the matrix – the aluminum alloy, as well as to characteristics of the classical metal-matrix composites with a single reinforcing material. Those characteristics depend on the volume fractions of the reinforcing components, sizes of the reinforcing particles, as well as on the fabrication process of the hybrid composites. The considered tribological characteristics are the friction coefficient and the wear rate as functions of the load levels and the volume fractions of the graphite and the SiC particles. The wear rate increases with increase of the load and the Gr particles content and with reduction of the SiC particles content. The friction coefficient increases with the load, as well as with the SiC particles content increase.

Abrasive wear mechanisms of fluoropolymer based composite coatings on aluminium substrates

Wear ◽  
1996 ◽  
Vol 200 (1-2) ◽  
pp. 122-136 ◽  
Author(s):  
M.Q. Zhang ◽  
K. Friedrich ◽  
K. Batzar ◽  
P. Thomas
Keyword(s):  
Abrasive Wear ◽  
Wear Mechanisms ◽  
Composite Coatings
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