scholarly journals On the Microstructure, Strength, Fracture, and Tribological Properties of Iron-Based MMCs with Addition of Mixed Carbide Nanoparticulates

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 2892 ◽  
Author(s):  
Grzegorz Królczyk ◽  
Eugene Feldshtein ◽  
Larisa Dyachkova ◽  
Mariusz Michalski ◽  
Tomasz Baranowski ◽  
...  

In this paper, the features of the strength, fractures, and tribological behavior of metal-matrix composites based on the FeGr1 material are discussed. To improve the material properties, a mixture of SiC, Al2O3 and C nanoparticulates have been added to an iron-based matrix. The simplex lattice design method and hardness, compression, and bending tests were used to determine the mechanical properties. Scanning electron microscopy was applied for fracture features analysis. Different fracture types, mainly trans-crystalline quasi-brittle and brittle fracture or inter-granular fracture and microcracks were registered for the composites tested. Depending on the type and amount of ceramic additives, significant changes in strength, as well as in the fracture features of the metal-matrix composites (MMCs), were observed. Based on tribological tests, changes in the momentary coefficients of friction, temperature of the friction surface, and wear rate of the composites with nanoparticulates were described. An analysis of the worn surface morphology revealed changes in the wear process depending on the MMC composition. It was shown that the use of hybrid mixed additives based on hard ceramic nanoparticulates improved both strength and tribological properties of composites.

Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 889
Author(s):  
Yelong Xiao ◽  
Pingping Yao ◽  
Haibin Zhou ◽  
Zhongyi Zhang ◽  
Taimin Gong ◽  
...  

A sensitivity analysis of braking speed and normal load on tribological properties of copper metal matrix composites (Cu-MMCs) was investigated using a subscale dynamometer. The morphologies of the worn surface and subsurface were observed by a scanning electron microscope and 3D video microscope. The results indicated that temperatures on the Cu-MMC surface increased with increasing the braking speed and normal load. The average coefficient of friction gradually decreased as the braking speed or normal load increased, and a slight decrease in the wear rate with increasing the braking speed up to 17 m/s after which a clear increasing trend was observed. As the normal load increased from 612 N to 1836 N, the wear rate decreased firstly and then promptly decreased. The transition in wear mechanism of Cu-MMC significantly depended on braking speed and normal load.


Author(s):  
Theerkka tharaisanan Rajamanickam ◽  
Kathiresan Marimuthu

Aluminium metal matrix composites (AMMC’s) have been widely used because of their superior properties like high strength to wear ratio, high wear resistance, and higher heat conduction rate. The additions of reinforcements in the form of discontinuous particles lead to an increase in the properties of Metal Matrix Composites (MMC). In this present work, the ALMMC composite was fabricated with the addition of discontinuous reinforcement particles of Zirconium Carbide (ZrC) and Boron Carbide (B4C). The mechanical properties such as tensile strength, hardness, and impact strength were tested as per the ASTM standards. The tribological properties were tested using a pin-on-disc setup under different loading conditions (10, 20, 30, 40 N). Moreover, the morphological characterization of ALMMC was carried out by using the Scanning Electron Microscope (SEM) analysis. Furthermore, the Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) was accomplished to find the thermal stability of ALMMC. The findings show that the variations of reinforcement of ZrC added had given improved properties like hardness, tensile strength, impact strength and wear resistance.


1979 ◽  
Vol 101 (1) ◽  
pp. 3-11 ◽  
Author(s):  
Turgay Ertu¨rk ◽  
Howard A. Kuhn

Fundamental deformation and fracture behavior of fiber-reinforced metal-matrix composites under deformation processing conditions were determined using upset tests on rectangular specimens. Defects that occur during simulated forging of a 2024 Al-alloy matrix reinforced with 25v/o stainless steel wires were characterized, and forming limit criteria for their prediction and prevention established. These criteria, determining the limits of deformation, provided guidelines for development of a process for forging an airfoil shape from the composite system studied. To this end, the limiting criteria were combined with an analysis of the flow of metal during forging. The forging design method developed, based on the forming limit criteria, demonstrates a rational approach to the design of processes for forging complex shapes from composite materials. Utilizing this approach, process parameters (die and preform geometry, lubrication) can be evaluated for forging sound complex composite shapes.


2020 ◽  
Vol 9 (1) ◽  
pp. 20190173 ◽  
Author(s):  
G. B. Veeresh Kumar ◽  
D. Gopinath Reddy ◽  
C. Vineeth Reddy ◽  
Ch Sriteja ◽  
R. Pramod

Sign in / Sign up

Export Citation Format

Share Document