Wear Characteristics and Adhesion Behavior of Calcium Phosphate Thin-Films

2010 ◽  
Vol 443 ◽  
pp. 469-474 ◽  
Author(s):  
Mohd Hamdi Bin Abdul Shukor ◽  
J.A. Toque ◽  
A. Ide-Ektessabi

Wear resistance is an important mechanical property expected from coatings intended for any type of applications. Understanding of this quantity is very practical because in real situations, coatings are subjected to repeating loads experienced not in a gradual orderly fashion but abruptly and indeterminately. This study looked into the wear characteristic and adhesion behavior of calcium phosphate, a known bioceramics, and hopes to provide better understanding of these properties. Radio frequency-magnetron sputtering (RF-MS) was used to deposit thin film (CaP) on glass. The coatings were subjected to single-pass microscratch and multi-pass wear test while monitoring the depth, load and displacement in situ. The results have shown that the changes in the surface topography can give an indication of the wear resistance of CaP. Coatings with good adherence to the substrate have shown less alteration of its surface roughness, measured in terms of Ra values, even after several scratch passes. The study on the different parameters revealed that deposition time is the most influential factor in CaP wear behavior. This was attributed to its correlation with coating thickness. Analysis of variance (ANOVA) also suggested that the other sputtering parameters studied in the experiments (argon pressure and RF power) did not have very significant effect on the wear pattern of the CaP thin films.

Author(s):  
Deepak Mehra ◽  
M.M. Mahapatra ◽  
S. P. Harsha

The purpose of this article is to enhance the mechanical properties and wear resistance of the RZ5 alloy used in the aerospace application by adding TiC particles. The present study discusses processing of in-situ RZ5-TiC composite fabricated by self-propagating high temperature (S.H.S.) method and its wear behavior. The effects of TiC particle on mechanical and microstructural properties of the composite are studied. The wear test is performed by varying the sliding distance and applied load. The composite is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results exhibited the properties like strength and hardness of RZ5-10wt%TiC composite has been increased considerably, while grain size is decreased as compared to the RZ5 alloy. The fractography indicated mixed mode (quasi-cleavage and ductile feature) failure of the composites. The wear results showed improvement in wear resistance of the composite. The FESEM showed dominate wear mechanisms are abrasion, ploughing grooves.


Author(s):  
Dongbo Wei ◽  
Fengkun Li ◽  
Xiangfei Wei ◽  
Tomasz Liskiewicz ◽  
Krzysztof J Kubiak ◽  
...  

In this study, surface Cr-Nb alloying was realized on γ-TiAl using double glow plasma hollow cathode discharge technique. An inter-diffusion layer was generated under the surface, composed of Cr2Nb intermetallic compounds. After Cr-Nb alloying, the surface nanohardness of γ-TiAl increased from 5.65 to 11.61 GPa. The surface H/E and H3/E2 increased from 3.37 to 5.98 and from 0.64 to 4.15, respectively. Cr-Nb alloying and its effect on fretting wear were investigated. The surface treatment resulted in improved plastic deformation and fretting wear resistance of γ-TiAl. The fretting wear test showed that an average friction coefficient of γ-TiAl against Si3N4 ball was significantly decreased after Cr-Nb alloying. The fluctuation of friction coefficient during running-in stage was significantly improved. The friction behavior of both γ-TiAl before and after Cr-Nb alloying could be divided into distinctive stages including formation of debris, flaking, formation of crack, and delamination. It was observed that the high hardness, resistance to plastic deformation, and fatigue resistance of γ-TiAl after Cr-Nb alloying could inhibit the formation of debris and delamination during friction test. The fretting wear scar area and the maximum wear scar depth were decreased, indicating that the wear resistance of γ-TiAl has been greatly improved after Cr-Nb alloying. The results indicated that plasma surface Cr-Nb alloying is an effective way for improving the fretting wear resistance of γ-TiAl in aviation area.


2011 ◽  
Vol 415-417 ◽  
pp. 170-173
Author(s):  
Jing Wang ◽  
Si Jing Fu ◽  
Yi Chao Ding ◽  
Yi San Wang

A wear resistant TiC-Cr7C3/Fe surface composite was produced by cast technique and in-situ synthesis technique. The microstructure and dry-sliding wear behavior of the surface composite was investigated using scanning electron microscope(SEM), X-ray diffraction(XRD) and MM-200 wear test machine. The results show that the surface composite consists of TiC and Cr7C3as the reinforcing phase, α-Fe and γ-Fe as the matrix. The surface composite has excellent wear-resistance under dry-sliding wear test condition with heavy loads.


Crystals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 682
Author(s):  
Liang Sun ◽  
Wenyan Zhai ◽  
Hui Dong ◽  
Yiran Wang ◽  
Lin He

Cr3C2-Ni cermet is a kind of promising material especially for wear applications due to its excellent wear resistance. However, researches were mainly concentrated on the experiment condition of room temperature, besides high-temperature wear mechanism of the cermet would be utilized much potential applications and also lack of consideration. In present paper, the influence of Mo content on the high-temperature wear behavior of in-situ Cr3C2-20 wt. % Ni cermet was investigated systematically. The friction-wear experiment was carried out range from room temperature to 800 °C, while Al2O3 ceramic was set as the counterpart. According to experimental results, it is indicated that the coefficient of friction (COF) of friction pairs risen at the beginning of friction stage and then declined to constant, while the wear rate of Cr3C2-20 wt. % Ni cermet risen continuously along with temperature increased, which attributes to the converted wear mechanism generally from typical abrasive wear to severe oxidation and adhesive wear. Generally, the result of wear resistance was enhanced for 13.4% (at 400 °C) and 31.5% (at 800 °C) by adding 1 wt. % Mo. The in-situ newly formed (Cr, Mo)7C3 ceramic particle and the lubrication phase of MoO3 can effectively improve the wear resistance of Cr3C2-20 wt. % Ni cermet.


2014 ◽  
Vol 541-542 ◽  
pp. 263-267
Author(s):  
S. Baskaran ◽  
B.M. Muthamizh Selvan ◽  
V. Anandakrishnan ◽  
R. Venkatraman ◽  
Muthukannan Durai Selvam

The AA7075-4%TiC metal matrix composite produced through in-situ casting technique was hot extruded and subjected to annealing at 415°C for 150 minutes. Another set of hot extruded AA7075-4%TiC metal matrix composite was heat treated to T6 condition. Dry sliding wear test was conducted with different sliding speeds and loads for both annealed and T6 conditioned composites to compare their wear behaviour. It was observed that irrespective of the heat treatment conditions, the depth of wear, decreases with increasing sliding velocity for all the loads tested and increases with increasing load for all the sliding velocities.


2006 ◽  
Vol 510-511 ◽  
pp. 562-565
Author(s):  
Jeng Wan Yoo ◽  
Kwon Yeong Lee ◽  
Ji Hui Kim ◽  
Ki Soo Kim ◽  
Seon Jin Kim

A new iron-based wear resistance alloy was developed to replace the Co-containing Stellite 6 alloys in nuclear power industry. The effect of B addition on the wear resistance was investigated. Sliding wear tests of Fe-Cr-C-Si-xB (x = 0.0, 0.3, 0.6, 1.0 and 2.0 wt%) alloys were performed in air at the room temperature under a contact stress of 103 MPa. Low-boron alloys containing less than 0.6 wt% boron showed an excellent wear resistance than any other tested alloys. The improvement was associated with the matrix hardening by promotion of the γ→α′straininduced martensitic transformation occurring during the wear test. However, the alloys containing more than 1.0 wt% boron showed slightly increased wear loss compared to the low-boron alloys because of the absence of the strain-induced martensitic transformation and the presence of the brittle FeB particles, aiding crack initiation.


2016 ◽  
Vol 68 (4) ◽  
pp. 476-481 ◽  
Author(s):  
Harun Mindivan

Purpose This study aims to investigate the microstructure and the abrasive wear features of the untreated and pack borided GGG 50 quality ductile iron under various working temperatures. Design/methodology/approach GGG 50 quality as-cast ductile iron samples were pack borided in Ekabor II powder at 900°C for 3 h, followed by furnace cooling. Structural characterization was made by optical microscopy. Mechanical characterization was made by hardness and pin-on-disc wear test. Pin-on-disc test was conducted on a 240-mesh Al2O3 abrasive paper at various temperatures in between 25 and 450°C. Findings Room temperature abrasive wear resistance of the borided ductile iron increased with an increase in its surface hardness. High-temperature abrasive wear resistances of the borided ductile iron linearly decreased with an increase in test temperature. However, the untreated ductile iron exhibited relatively high resistance to abrasion at a temperature of 150°C. Originality/value This study can be a practical reference and offers insight into the effects of boriding process on the increase of room temperature wear resistance. However, above 150°C, the untreated ductile iron exhibited similar abrasive wear performance as compared to the borided ductile iron.


Author(s):  
Akshay Shinde

Abstract: To improve the wear resistance of the hybrid powder coating, TiO2 nanoparticles was hot mixed to form a homogenous mixture with the powder in the range varying wt. dry sliding wear test conducted to determine the wear resistance. The experiments were design according to Taguchi L9 array to find the optimum nanoparticles content required to minimize the wear rate of the coating. ANOVA was used to determine the effect of the parameters on wear rate. It showed that reinforcement has the maximum contribution on the wear rate of the coating as compared to load and frequency. From the graph of means optimum parametric values was obtained at 2 % wt of reinforcement, 2 N load and 2 Hz frequency. The wear rate decrease with the increase in reinforcement. Keywords: Taguchi Method, Tribometer, Hybrid powder, TiO2, Wear Rate.


2020 ◽  
Vol 184 ◽  
pp. 01018
Author(s):  
A Rohit Sai Krishna ◽  
B Vamshi Krishna ◽  
D Harshith ◽  
T Sashank ◽  
Ram Subbiah

This project investigates on salt bath nitriding process in order to improve the wear behavior of the material. This process increases the hardness of the material. The specimens were nitrided at 580°c on three different timing hours such as 60 minutes, 90 minutes & 120 minutes. A pin on disc machine is used to conduct wear test, so that wear loss can be determined. The specimens are to be magnified by metallographic test like scanning electron microscope. The untreated specimen is used to compare with the nitrided specimen. The best specimen is chosen which determines the life of material & improves the better wear resistance. The hardness of untreated material and nitrided material are compared. The material AISI stainless steel has many unique properties but it lacks wear resistance and hardness because of which it has limited applications. By conducting heat treatment operation, the hardness of the material does not improve, but by conducting case hardening process the hardness of the outer case will be high compared to base metal. If the hardness and wear resistance of the material improves the material can be used in wide range of applications.


Author(s):  
Yasser Fouad ◽  
Khaled M. Ibrahim ◽  
Brando Okolo

First results of the influence of Equal Channel Angular Pressing (ECAP) on the wear behavior of the magnesium alloy AZ80 have been discussed. The evident grain refinement and redistribution of second phases in the 4 pass processed materials resulted in an increase of the hardness state in the AZ80 alloy. Wear tests conducted on a pin-on-disc set-up revealed better wear resistance for the 4 pass processed materials. Isothermal aging treatment, at 210°C for 10 hrs, of the ECAP processed materials showed that wear resistance properties are improved markedly. For incremental sliding speeds during the wear test, wear rate of the AZ80 alloy was found to increase.


Sign in / Sign up

Export Citation Format

Share Document