Yusuf Şahin

Analysis of abrasive wear behavior of PTFE composite using Taguchi’s technique

Abstract Polymeric composites are widely used for structural, aerospace, and automobile sectors due to their good combination of high specific strength and specific modulus. These two main characteristics make these materials attractive, compared to conventional materials like metal or alloy ones. Some of their typical benefits include easy processing, corrosion resistance, low friction, and damping of noise and vibrations. Wear behavior of Polytetrafluoroethylenes (PTFE) and its composites including glass-filled composites and carbon-filled composites are investigated using a pin-on-disc configuration. A plan of experiments in terms of Taguchi technique is carried out to acquire data in controlled way. An orthogonal array (L9) and the analysis of variance are employed to investigate the influence of process parameters on the wear of these composites. Volume loss increased with abrasive size, load, and distance. Furthermore, specific wear rate decreased with increasing grit size, load, sliding distance, whereas, slightly with compressive strength. Optimal process parameters, which minimize the volume loss, were the factor combinations of L1, G3, D1, and C3. Confirmation experiments were conducted to verify the optimal testing parameters. It was found that in terms of volume loss, there was a good agreement between the estimated and the experimental value of S/N ratio with an error of 1.604%. Moreover, abrasive size, load, and sliding distance exerted a great effect on the specific wear rate, at 51.14, 27.77, and 14.70%, respectively.

Wear Behavior of Al-Al2O3 Reinforced Composites

Aluminum composites containing 10wt. % of Al2O3 with 3 µm size of particles have been produced using powder metallurgy (PM) method and wear behavior of the composites were tested under dry condition. A comparison is also made with SiCp reinforced Al composite produced at the same conditions. The wear rate of both types’ composites increased with all applied loads, but wear rate of the composites was a strong function of normal load rather than that of type of particles used for the manufacturing MMCs. Furthermore, the wear rate of Al-Al2O3 composite was smaller than that of Al-SiCp reinforced composite, but not indicating significant differences on it. Moreover, SEM examination showed that plastic deformation was the dominant type of wear for the Al2O3 particle reinforced MMCs, but the fragmented-deformed layer of particles was more effective for the SiCp reinforced MMCs due to more fracturing of particles.

Tribological behavior of Al2O3 and B4C particle-reinforced copper matrix investigated by the Taguchi method

Abstract There are many technical applications in which wear is a critical issue. Copper can be filled with particulate materials to enhance the tribological behavior, mechanical and physical properties as well. Copper matrix containing 10 vol.-% Al2O3 and B4C particles were produced using the powder metallurgy method and their dry wear behavior was investigated at different sliding conditions against a hardened alloy steel counterface using Taguchi technique. Four control factors like lubrication, load, sliding distance and hardness were designed in a L18 factorial orthogonal array for the experiments to investigate the wear behavior of the metal matrix composites. Moreover, a correlation derived from the results of Taguchi experimental design was proposed, resulting in a predictive equation for estimation of these properties. The experimental results showed that the weight loss was highly influenced by the lubrication factor, followed by the load factor. However, these were then followed by hardness and sliding distance. The estimated weight loss was calculated and a good agreement was observed between the predicted and actual weight loss at a confidence level of 90%. The wear resistance was significantly better for B4C particle-reinforced composites than that for the Al2O3 particle-reinforced composites. Moreover, the results were approved by scanning electron microscope micrographs of worn surfaces of the samples.

The Effect of B4C Additions on Mechanical Properties of Fe-Cu-Co Matrix Composites for Diamond Tools

The effects of boron carbide (B4C) additions on characteristic of diamond impregnated Fe-Co-Cu matrix composites have been investigated using powder metallurgy (PM) method. For this purpose, samples of Fe-(30-60)wt. % Cu–20 wt. %Co alloys and1wt. % B4C additions of its matrix were processed by cold pressing at 350 MPa, followed by sintering at 1100°C. Microstructural examination, hardness and wear tests were performed.The microstructure of Fe–Cu–Co alloys was very sensitive to the Cu content and pore closure took place with increasing the Cu content.In addition, the addition of B4C particles increased Fe–Cu-Co hardness about 44% compared to samples without B4C particles. The experimental results showed that alloy Fe–60 wt. % Cu–20 wt. %Co-1 wt. % B4C presented the best results for use in diamond cutting tools.

S/N Ratio Analysis of Tribological Behavior of SiCp Reinforced Al2124 Based Metal Matrix Composite

Al2124-20wt.% SiCp composites were prepared by powder metallurgy (PM) method and investigated the tribological behavior of MMCs. S/N ratio analysis and analysis of variance (ANOVA) were employed to investigate which design parameters significantly affected the wear of the composites. The hardness of the matrix alloy increased from 44.2 HRB up to 87 HRB when reinforced with SiC particles. The ANOVA results showed that the hardness exerted the greatest effect on the wear, followed by the abrasive size.

The Microstructure and Hardness of Al2O3 Particle Reinforced Composite

Aluminium alloys (Al2014 and Al2124 alloy) and their composites containing 10wt.% Al2O3 with 3 µm and 43 µm sizes of particles have been produced by powder metallurgy (PM) method and the microstructure and hardness were investigated. Scanning electron microscopy (SEM) investigation showed a nearly uniform distribution of the Al2O3 particles within the Al2124 alloy matrix although some porosities were found in the Al2014 alloy matrix. Furthermore, it was found that the macrohardness of Al2124 alloy composite improved highly in comparison to that of Al2014 alloy due to fine of microstructure and increased hardness. The hardnesses of both MMCs increased with increasing the particle sizes.

Wear Behavior of Diamond+SiCp-Reinforced Metal Matrix Composite by Taguchi Method

Fe-Co based diamond-reinforced composites (D-MMCs) and diamond+SiC-reinforced composites (D+SiC-MMCs) were produced by cold pressing method. Investigation of the wear behaviors on two-body abrasive wear behavior of the composites were carried out under different conditions. 2k factorial designs of experiments were used to obtain the data in a controlled way. The wear parameters studied were sliding speed, load and sliding distance. An orthogonal array and analysis of variance (ANOVA) were employed to investigate the influence of process parameters on the wear resistance of these composites. The results indicated that the incorporation of SiC particles in the metal matrix as a secondary reinforcement increased the wear resistance. In addition to this, the applied load had the significant effect on the weight loss of both types of composites. Furthermore, a correlation was derived from the results of the experimental design by multiple regressions. Finally, confirmation of experiment was conducted to verify the predicted model.