In this study, aging temperature effect on the fracture mode and wear mechanism of the (HADFIELD) STEEL was investigated. For this purpose, 5 blocks were casted from (HADFIELD) STEEL. After the casting, all blocks austenitized in 1100° C for 2 hours and immediately quenched in the pure water. Then, one block at austenitising conditions remained and four other blocks the aging heat treatment in 450, 500, 550 and 600° C for 1 hours. In the next step, uniaxial tensile, hardness measuring by Vickers method and wear by pin-ondisk method tests were applied on them. To evaluation of the microstructures was conducted by optical microscopy and the fractured surfaces and wear mechanism were observed by scanning electron microscopy. Optical microscopy observations showed that the aging heat treatment temperature increase, leads to increases carbide precipitates and decreasing austenite grains size in the (HADFIELD) STEEL microstructure. The results of mechanical tests showed that aging temperature increase lead to increase in hardness, strength and wear resistance of (HADFIELD) STEEL, but in return reduces fracture strain. Also, scanning electron microscopy images from wear and fractured surfaces showed that aging temperature increase lead to the creation of brittle fracture and in all aged samples sticky wear took place.

In this study, effects of using quenching in aqueous salt solution, on the corrosion behavior of (HADFIELD) MANGANESE STEEL was investigated. For making MANGANESE STEEL according to ASTM A-128C standard, initially two Y-shaped aluminum models prepared and then castings made through Sodium Silicate/CO2 procedure by closed feeding method. Melting was conducted in non-core induction furnace. After the casting, both samples austenitized in 1100oC for 2 hours and then one block quenched in pure water and the other quenched in the aqueous 3.5% salt solution. To evaluate the corrosion behavior of samples, potentiodynamic polarization and electrochemical impedance spectroscopy methods in the 3.5% NaCl solution were used. The results of both methods indicates corrosion resistance of salt bath quenched sample is significantly higher than the other. This is due to:a)-salt solution quenching medium decreased the amount of carbides in the microstructure and prevented the formation of galvanic cell.b)- Quenching in salt solution increased the solubility of carbon in the austenite phase that caused the reducing the amount of grain boundaries.

MANGANESE STEELs have extensively application in industries due to good resistance to wear, high work hardening capability with high toughness and ductility. Heat treatment is the main process to obtain desired mechanical properties and microstructure in this STEEL. The austenitizing temperature, the austenitizing time and the rate of quenching by increasing salt content are the main factors in heat treatment. For dissolving of carbide, the austenitizing temperature and austenitizing time are very important. Quenching rate must be high for minimizing the grain boundary carbids. In this research the effects of these input parameters on the grain boundary carbide content, austenite grain size and hardness have been critically analyzed using Taguchi method. In the optimization by Taguchi approach, L9 (3)3 array, employing nine experiments, with three levels for each factor, was chosen for DOE. It has been found that the austenitizing temperature is the most important process parameter affecting the carbide content, grain size and hardness. The heat treatment produces the minimum carbide content and low grain size when the process parameters were set at their optimum values. It has been shown that heat treatment parameters set as their optimum levels can ensure significant improvement in the objectives.

In this study, effect of aluminum alloying element on KIC and ac of (HADFIELD) hypereutectoid STEEL was investigated by using the impact test results. For this purpose, initially 2 casting blocks were prepared from (HADFIELD) STEEL (without addition of Al and with 1.68 wt% Al) by using coreless induction furnace. After casting, all blocks were austenitized in 1100oC for 2 hours and immediately quenched in pure water. In the next step, uniaxial tensile test, Vickers hardness test and Charpy impact test were applied on specimens at room temperature. Evaluation of microstructures were conducted by optical microscopy and the fractured surfaces were observed by scanning electron microscope. The results of impact tests and fracture toughness empirical relationships were used to evaluate the KIC and ac of the (HADFIELD) STEEL. The optical microscopy images indicated that by increasing the amount of aluminum in the chemical composition of (HADFIELD) MANGANESE austenitic STEEL, austenite grains size increased from 111.9 to 142.5 micrometer. The results of tensile test, hardness test and impact test represents an increase in yield strength and hardness, and reduction of failure strain and impact energy of (HADFIELD) STEEL because of adding aluminum to its composition. Calculations of fracture toughness and critical crack length for (HADFIELD) STEEL showed that the addition of aluminum to STEEL leads to reduction of fracture toughness from 163.7 to 104.5 Mpa. (m)1.2 and reduced the critical crack length at surface from 0.014 to 0.007m.

In this paper, the wear behavior of (HADFIELD) STEEL has been investigated by using the grinding wheel in the pin on disk test method. The main parameters of this test method such as normal load on pin, sliding speed and sliding distance have been studied. In this test, the main and interaction effects of parameters on the weight loss and its regression models have been obtained. The results show that chipping and surface cracking are two basic mechanisms of wear of the STEEL. In addition, the normal load is more effective than sliding speed in weight loss of the STEEL. In addition, the role of normal load on the weight loss increases with increasing the sliding distance, while the role of disk velocity fixes. The normal pressure (load) must also be lower than 0.5 MPa for low stress wear condition.

In this study the for survey effect of titanium on the microstructure and properties of STEEL adfield, 4 alloy composition based Containing 1.2 percent carbon and 12 percent MANGANESE and different amounts of titanium (0.2, 0.4 and 0.6) and a sample without titanium for compared were foundery. Solution heat treated specimens were including austenitizing to 1100oc temperature for three hours and then quench in water. To investigate the microstructure used of optical microscopy and scanning electron microscopy (SEM) and to determine the type of carbides was used elemental analysis(EDX). for wear test was used The pin on disk method. Results from observations and experiments showed that the structural heat threatment completely austenitized (in the sample of No titanium) and non-continuous carbides of titanium in austenitic background (in the sample contain of titanium) were obtained. Increasing titanium, fine grain structure and hardness has increased. In addition to the large difference in the wear resistance of titanium and non-titanium samples obtained. The best wear resistance obtained  of the sample with 0.6% of titanium.

In this paper, the effect of aluminum addition on the tribological behavior of (HADFIELD) STEEL in mild wear condition was investigated. The pin-on-disk test method was used on the different compositions of (HADFIELD) STEEL that alloyed by three nominal compositions of zero, 1.5 and 3 weight percent of aluminum. The experimental induction furnace surrounded by Ar atmosphere and zirconia ceramic mold was used for melting and casting of samples. In the wear test, the grinding wheel as abrasive medium was used and the changes in the friction coefficient and the weight losses of specimens versus the sliding distance were measured. The tensile, hardness and impact tests were used for evaluation of mechanical properties. In addition, the microscopically studies on the deformed samples, worn surface and wear debris were done using optical and scanning electron microscopes. The results shown that in the low stress wear condition, the work-hardening of worn surface of (HADFIELD) STEEL cannot well be activated, therefore it has not sufficient wear resistant. By addition of 3wt. % aluminum, the yield strength from 415MPa to 470MPa and hardness from 190HV to 215HV can be increased. In addition, depth of work-hardened on abrasive forces and worn surface hardness can be enhanced from 100mm to 200mm and from 340HV to 365HV in sequence. Thus the wear rate from 0.15mg/m to 0.11mg/m was decreased and wear resistance was improved up to 70%.

In this study, effect of chromium addition on the fracture toughness of (HADFIELD) STEEL was investigated by using charpy impact test. For this purpose, 3 casting blocks were prepared from (HADFIELD) STEEL (without Cr addition, and containing 1. 5% Cr and 3% Cr) by using coreless induction furnace. After casting, all blocks austenitized in 1100° C for 2 hours and immediately quenched in the pure water. In the next step, uniaxial tensile test, hardness test and charpy impact test were applied on specimens. Evaluation of the microstructures was conducted by optical microscope and the fractured surfaces were observed by scanning electron microscope. The results of charpy impact test and fracture toughness empirical relationships were used for determination of fracture toughness values of specimens. As a result, it was found that sample without Cr had lowest hardness – highest fracture toughness value – highest critical crack length and the sample containing 3% Cr had the highest hardness – lowest fracture toughness value – lowest critical crack length. Also, scanning electron microscope images indicated increasing crack growth in the charpy impact test specimens by addition of Cr to chemical composition of (HADFIELD) MANGANESE STEEL.

Standard MANGANESE STEEL or (HADFIELD) STEEL is a non-magnetic alloy of iron, MANGANESE, carbon with a composition of 1.0-1.4% carbon and 10-14% MANGANESE. It is important to maintain the ratio of MANGANESE to carbon in this STEEL. The good abrasion resistance, microstructure and hardenability are the main properties of these STEELs. The important limitations in the production of high MANGANESE STEEL parts, are formation of coarse MANGANESE-carbides during the solidification process, and partially solution of carbides in microstructure during solution annealing heat treatment. In this research, the effects of increasing zirconium alloy element and the effect of solution annealing heat treatment on microstructure and abrasion resistance of MANGANESE STEELs is investigated by analyzing microstructure and wear conditions Wear test was carried out at 500, 1000 and 1500 meters distance. The wear test results showed that Zr can modify wear resistant in as cast and solution treatment conditions. The microstructure assessment results shows that increasing of Zirconium element increase solution tendency of carbides in as cast and heat treated condition, and modify remained carbide sizes and distribution in Zr content STEELs especially in 0.25% Zr.

In this study, the effect of aluminum alloying element on the microstructural changes, mechanical properties and fatigue life of (HADFIELD) STEEL was investigated. For this purpose, 2 blocks castings were prepared from (HADFIELD) STEEL (without Al and with 1. 68 wt% Al addition) by using coreless induction furnace. After the casting, all the blocks were austenitized in 1100° C for 2 hours and immediately quenched in the pure water. In the next step, uniaxial tensile test, bending fatigue test and hardness test by vickers method were conducted on specimens. Microstructure evaluation was conducted by optical metallography and the fractured surfaces were observed by scanning electron microscopy. As a result, it was found that the sample containing 1. 68 wt% Al had more hardness and greater yield strength but tensile strength, flexibility and fatigue life of lesser compared to sample without Al addition. So, scanning electron microscopy images indicated the occurrence of ductile fracture in tensile test for both samples and was increased fatigue crack growth in the fatigue test due to the addition of aluminum to chemical composition of (HADFIELD) STEEL.