Microstructure and Wear Property of Zn-Al Alloy Reinforced with Carbonized Rice Husks

2012 ◽  
Vol 463-464 ◽  
pp. 494-498
Author(s):  
Su Qiu Jia ◽  
Yun Hai Ma ◽  
Jin Tong ◽  
Guo Jun Liu

Zn-Al composites with carbonized rice husks were prepared by permanent mould. Microstructure and wear property of Zn-Al composites were measured under the condition of as-cast heated at 375 °C and 430 °C corresponding to solid and semi-solid range. The microstructure of as-cast, heated at 375 °C and 430 °C were different. The microstructure of as-cast Zn-Al alloy revealed primary a dendrites (α) and eutectoid α+η (α,rich Al, η rich Zinc)phases. The microstructure of ZA alloy with carbonized rice husks was fine dendrites for heated at 375 °C and second and third dendrites were almost dispersed. After semi-solid treatment, the microstructure of Zn-Al composites presented quasi-round or round and large with time prolonger. The hardness of Zn-Al composites rose with carbonized rice husks and increased slightly by heat treatment. Wear resistance of Zn-Al composites with carbonized rice husks improved significantly and increased with carbonized rice husks. But at the same amount of carbonized rice husks the wear resistance of the composite varied little regardless of being in the state of as-cast or heat treatment.

2019 ◽  
Vol 961 ◽  
pp. 118-125
Author(s):  
Muhammad Syukron ◽  
Zuhailawati Hussein ◽  
Abu Seman Anasyida

The combination of heat treatment, addition of grain refiner and ECAP processing is used to improve mechanical properties and wear resistance of A356 Al alloys with 1.5 wt.% TiB2. The alloys were grouped into as-cast and pre-ECAP annealing. The alloys were characterized with hardness and wear testing, optical microscopy and SEM. The ECAP processing was done through BA route for 4 passes and it improved hardness, distribution of TiB2 and Si particles in the aluminium matrix and increased wear resitance of pre-ECAP annealing specimen.


2014 ◽  
Vol 680 ◽  
pp. 11-14
Author(s):  
Ke Ren Shi ◽  
Sirikul Wisutmethangoon ◽  
Jessada Wannasin ◽  
Thawatchai Plookphol

In this study, semi-solid Al-Mg-Si alloy (AC4C) was produced by using the Gas Induced Semi-Solid (GISS) die casting process. The tensile strength and ductility of the semi-solid die cast Al alloy (GISS-DC) after T6 heat treatment were investigated and compared with those of the conventional liquid die casting (CLDC). The microstructures of GISS-DC and CLDC observed by an optical microscopy were presented. The ultimate tensile strength (UTS) and yield strength (0.2% YS) of GISS-DC are compatible with those of the CLDC. However, the GISS-DC has better ductility than the CLDC, this may be due to the smaller and more globular primary α-Al phase and rounder shaped-Si particle microstructures presented in the GISS-DC. Common shrinkage pores and defects were also observed by SEM from the fracture surfaces of both alloys.


Author(s):  
K. Raju ◽  
N. Gopi Krishna ◽  
L. Sankara Rao ◽  
S. N.Ojha

In the present study the microstructural features and tribological characteristics of hot forged A356 Al alloy subjected to SIMA (Strain induced melt activation) and T6 heat treatment (semi-solid) processes have been investigated. The SIMA process consists of hot forging of alloy at 325˚C followed by cold forging at room temperature, isothermal holding at 580˚C for 10 min and quenching. In case of T6 heat treatment, the hot forged alloy was solution treated at 540˚C for 4 hours followed by quenching in cold water and artificial aging at 155˚C for 3 hours. The microstructure of the alloy exhibited a spherical or globular morphology of the primary α-phase with uniform distribution of solutes in the interdendritic region. A detailed analysis of the solidification behaviour of the melt from semi-solid region of the alloy is reported. The reasons for the consequential changes in tribological properties of A356 Al alloy processed by SIMA andT6 heat treatment have been clearly brought out.


2020 ◽  
Vol 34 (25) ◽  
pp. 2050261
Author(s):  
Yingwu Wang ◽  
Xiaoqing Zuo ◽  
Songjiang Ran ◽  
Yushun Ye ◽  
Jihua Tian

The effects of semi-solid extrusion temperature change, extrusion pressure, SiC content and T5 heat treatment on the microstructure, mechanical properties, and wear resistance of SiC particle strengthened high aluminum zinc-base alloy [Formula: see text] composites were studied. The results show that semi-solid extrusion broke the dendrites of [Formula: see text] composites, refined their grain structure, and improved particle aggregation. The density, hardness, yield strength, tensile strength and elongation of [Formula: see text] composites first increased and then decreased when the extrusion temperature and SiC content increased, and also increased when the extrusion pressure rose. The optimal extrusion temperature, pressure and SiC content are 475[Formula: see text], 15 MPa and 10 wt.%, respectively. T5 heat treatment further refined the crystalline grains and promoted [Formula: see text] and [Formula: see text] to precipitate as strengthening phases, which improve the mechanical properties and wear resistance of [Formula: see text] composites. Consequently, the hardness, yield strength, tensile strength and elongation of the heat-treated composites improved by 18.99%, 9.66%, 4.93% and 9.76%, respectively. The wear loss of the heat-treated composites reduced by 31.65% under a load of 1600 N and a rotational speed of 200 r/min compared with the as-cast composites.


2011 ◽  
Vol 391-392 ◽  
pp. 620-624
Author(s):  
Yong Ying Du ◽  
Dan Jin

65Mn spring steel is mainly used for rotary blade which is a vulnerable part of farming machinery. The experiment of the wear-resistance property for 65Mn spring steel under different heat treatments is conducted. The results are discussed based on the regression orthogonal design. The wear-resistance property of 65Mn steel has been discussed by applying diverse heat treatment technology and the optimum parameters of heat treatment for the best anti-wear property are obtained through experiments. The influence of the parameters on anti-wear property is studied by applying the regression orthogonal design. The relation between the wear mass loss and diverse heat treatment parameters has been given by using planar and contour figure. The optimum heat treatment parameter for maximum anti-wear ability is obtained as following: 852.64 for quenching temperature, 18.36min for quenching time, and 145.44 for tempering temperature, respectively.


2011 ◽  
Vol 339 ◽  
pp. 714-717 ◽  
Author(s):  
Siriwan Pannaray ◽  
Sirikul Wisutmethangoon ◽  
Thawatchai Plookphol ◽  
Jessada Wannasin

The aim of this study is to determine the appropriate solution treatment temperature and time of semi solid 2024 Al alloy. Solution heat treatment at 450°C and 480 °C for various times, from 4 hours to 16 hrs, were applied followed by artificial aging at 220 °C for 1 hr. Microstructure of the semi solid cast 2024 aluminum alloy mainly showed globular grain structure which consisted of matrix-α (Al) and grain boundary (GB) - eutectic phases (α+Al2CuMg/Al2Cu). Eutectic GB phases was found to completely dissolved after solution heat treatment at 480°C for 14 hrs while sample solution treated at 450°C for the same time showed the existence of remaining GB phases. Prolonging heat treatment after 14 hrs at both temperatures resulted in the formation of coarse black particles at the grain boundaries which were identified as Mg2Si phases. Therefore the suitable solution treatment of the alloy in this study was at 480°C for 14 hrs.


2015 ◽  
Vol 798 ◽  
pp. 435-439
Author(s):  
S.D. Ambekar ◽  
Sandeep Kadam ◽  
S.A. Sonawane

This research is limited to study of wear resistance of 20MnCr5 (SAE 5120) alloy steel hardened by Carburizing and Cryogenics, which has wide application in industries like gears, shafts, bearings, pins etc. Cryogenics is used as a supplement treatment that is performed after carburizing. The abrasive wear study is performed on pin-on-disc tribotester. The counterface disc was kept same for both the heat treatments (carburizing and cryogenics). Sliding velocity of 0.8 m/s, 1.6 m/s, 2.4 m/s, Sliding Distance of 1200 m, 1400 m, 1600 m and Load of 3 kg, 4 kg and 5 kg were used to evaluate the wear resistance.


2020 ◽  
Vol 998 ◽  
pp. 48-54
Author(s):  
Kenta Kusumoto ◽  
Kazumichi Shimizu

This study investigated the influence of nickel (Ni) addition on erosive wear property of multi-component white cast iron with good erosive wear resistance. Multi-component white cast irons (MWCIs) with 2 mass % of carbon (C), 5 mass % of chromium (Cr), molybdenum (Mo), tungsten (W), niobium (Nb) and 0, 3, 5 mass % of Ni were prepared as experimental materials. The heat treatment condition was quenching by forced air cooling after keeping the specimens at 1123K for 3.6ks. Specimens with size of 50mm×50mm×10mm were tested using a suction-type blasting machine. The test was conducted with impact angle of 30, 60 and 90 deg. at room temperature. Collision particles were irregular steel grids with average particle diameter of 770μm and hardness of 810HV1. The speed of air flow was about 100m/s while the speed of impact particles was around 20.0g/s and the total time of each experiment was 3600 sec.. According to the result, erosion rate was decreased with the increase of Ni content in all of the impact angles. Especially, MWCIs which contain 5 mass % Ni showed the most excellent erosive wear resistance. As reasons, it can be considered that with Ni addition, the volume fraction of eutectic carbides and secondary carbides was increased which enhanced the matrix structure and suppressed the surface deformation of the experimental surface. Therefore, the increasing of eutectic carbides and secondary carbides can be considered as the reason of erosive wear resistance increased.


2016 ◽  
Vol 67 ◽  
pp. 05012
Author(s):  
N. Fathy ◽  
M. Ramadan ◽  
K. M. Hafez ◽  
A.S. Alghamdi ◽  
K. S. Abdel Halim

Metals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 596 ◽  
Author(s):  
Xiaobo Liu ◽  
Miao Yang ◽  
Dekun Zhou ◽  
Yuguang Zhao

In situ Mg2Si–Al composites were prepared by using gravity casting and semi-solid extrusion. After P modification, the primary Mg2Si transformed to polygonal blocks. Extraction tests showed that the Mg2Si crystals had octahedral and tetrakaidekahedral morphologies. The semi-solid microstructure of the double-spheroidized α-Al matrix and reinforced-phase Mg2Si was successfully obtained by using semi-solid extrusion. Extraction tests showed that the Mg2Si crystals had a spherical morphology. Dry sliding wear behaviors of in situ Mg2Si–Al composites fabricated by using gravity casting and semi-solid extrusion with isothermal heat treatment holding times of 50, 60, and 160 min against 45 steel, under conditions of different sliding speeds and loads, were investigated. The worn surfaces were analyzed using SEM and EDS techniques. The results showed that Mg2Si–Al composites fabricated by using semi-solid extrusion were superior in terms of wear resistance to Mg2Si–Al composites fabricated by using gravity casting, because the former had uniformly distributed spherical reinforced phase particles of Mg2Si with weaker stress concentration around the particles, delaying the generation and expansion of cracks. The Mg2Si particles were not easily detached from the matrix, and once they fell off, the Mg2Si particles only served as spherical abrasive grains, with relatively small cutting and wear properties for the composite material. It was found that the Mg2Si/Al composite fabricated by using semi-solid extrusion with an isothermal heat treatment holding time of 60 min had the best wear resistance. The failure mechanisms of Mg2Si/Al composites were found to be mainly adhesive wear and abrasive wear.


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