scholarly journals Characterization of Nanobainitic Structure Obtained in 100Crmnsi6-4 Steel after Industrial Heat Treatment/ Charakteryzacja Struktury Nanobainitycznej Wytworzonej W Handlowej Stali Łożyskowej – 100Crmnsi6-4 W Przemysłowej Obróbce Cieplnej

2014 ◽  
Vol 59 (4) ◽  
pp. 1637-1640 ◽  
Author(s):  
J. Dworecka ◽  
E. Jezierska ◽  
K. Rozniatowski ◽  
W. Swiatnicki
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Treatment Process ◽  
Tensile Tests ◽  
Bearing Steel ◽  
Transformation Kinetics ◽  
Transmission Electron ◽  
Microstructure Parameters ◽  
Static Tensile

Abstract The aim of the work was to produce a nanobainitic structure in the commercial bearing steel - 100CrMnSi6-4 and to characterize its structure and mechanical properties. In order to produce this structure the austempering heat treatment was performed, with parameters that have been selected on the basis of dilatometric measurements of phase transformation kinetics in steel. The heat treatment process was performed in laboratory as well as in industrial furnaces. The obtained structure was characterized using transmission electron microscopy. In order to investigate the effect of the microstructure parameters on the material’s mechanical properties, the hardness, impact strength and static tensile tests have been conducted.

scholarly journals Modification of Mechanical Properties of Aluminum Alloy Rods via Friction-Extrusion Method

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5224
Author(s):  
Anna Wójcicka ◽  
Krzysztof Mroczka ◽  
Jerzy Morgiel
Keyword(s):  
Mechanical Properties ◽  
Outer Zone ◽  
Tensile Tests ◽  
The Core ◽  
Transmission Electron ◽  
Gradient Microstructure ◽  
The Face ◽  
Static Tensile ◽  
Friction Extrusion ◽  
Extrusion Method

The elaboration of a modified friction-extrusion method aimed at obtaining 2017A aluminum rods of gradient microstructure is described. This was achieved by cutting spiral grooves on the face of the stamp used for alloy extrusion. The experiments were carried out at a constant material feed (~10 mm/min) and a range of tool rotation speeds (80 to 315 rpm). The microstructure observations were carried out using light microscopy (LM) and both scanning and transmission electron microscopy (SEM and TEM). The mechanical properties were assessed through hardness measurements and static tensile tests. The performed investigations show that material simultaneous radial and longitudinal flow, enforced by friction of the rotating tool head and extrusion, results in the formation of two zones of very different microstructures. At the perpendicular section, the outer zone stands out from the core due to circumferential elongation of strings of particles, while in the inner zone the particles are arranged in a more uniform way. Simultaneously, the grain size of the outer zone is refined by two to four times as compared with the inner one. The transfer from the outer zone to the core area is of gradient type. The hardness of the outer zone was found to be ~10% to ~20% higher than that of the core.

Characterization of Microstructure and Mechanical Properties of a Nb-Microalloyed Steel after Quenching-Partitioning-Tempering Process

2010 ◽  
Vol 654-656 ◽  
pp. 90-93 ◽  
Author(s):  
Xiao Dong Wang ◽  
Zheng Hong Guo ◽  
Yong Hua Rong
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Treatment Process ◽  
Microalloyed Steel ◽  
Heat Treatment Process ◽  
Step Process ◽  
Transmission Electron ◽  
Nb Microalloyed Steel ◽  
Tempering Process

A novel heat treatment process, that is, quenching-partitioning-tempering (Q-P-T) process, has been developed as a new way to obtain ultrahigh strength martensitic structural steel containing retained austenite and alloying carbide. In order to display merit of the Q-P-T process, a medium carbon Nb-microalloyed steel is treated by Q-P-T 1-step process and Q-P-T 2-step process, as well as treated by the transformation induced plasticity heat treatment process and quenching and tempering process, respectively. The results show that Q-P-T samples possess better mechanical properties than those treated by other heat treatment processes. The origin of the good mechanical properties is analyzed based on the phase and microstructure characterization using X-ray diffraction, scanning electron microscopy and transmission electron microscopy.

Characterization of Polypropylene Nanocomposite Structures

2006 ◽  
Vol 129 (1) ◽  
pp. 105-112 ◽  
Author(s):  
K. Kanny ◽  
V. K. Moodley
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Material Properties ◽  
Melt Blending ◽  
Transmission Electron ◽  
Low Weight ◽  
Static Tensile ◽  
Exfoliated Nanocomposite ◽  
Nanocomposite Structures

This study describes the synthesis, mechanical properties, and morphology of nanophased polypropylene structures. The structures were manufactured by melt-blending low weight percentages of montmorillonite nanoclays and polypropylene thermoplastic. Both virgin and infused polypropylene structures were then subjected to quasi-static tensile, flexural, hardness and impact tests. Analysis of test data show that the mechanical properties increase with an increase in nanoclay loading up to a threshold of 2wt.%; thereafter, the material properties degrade. At low weight nanoclay loadings the enhancement of properties is attributed to the lower percolation points created by the high aspect ratio nanoclays. The increase in properties may also be attributed to the formation of intercalated and exfoliated nanocomposite structures formed at these loadings of clay. At higher weight loading, degradation in mechanical properties may be attributed to the formation of agglomerated clay tactoids. Results of transmission electron microscopy studies and scanning electron microscopy studies of the fractured surface of tensile specimens verify these hypotheses.

Effect of Heat Treatment Process on Microstructure and Properties in Low Carbon Si-Mn Q&P Steel

2011 ◽  
Vol 233-235 ◽  
pp. 1009-1013
Author(s):  
Cai Zhao ◽  
Di Tang
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Retained Austenite ◽  
Treatment Process ◽  
Lath Martensite ◽  
Heat Treatment Process ◽  
Low Carbon ◽  
Transmission Electron ◽  
Partitioning Time

The mechanical properties of Low Carbon Si-Mn Q&P steel are strongly affected by the conditions of heat treatment. Microstructures and mechanical properties of Low Carbon Si-Mn Q&P steel at different partitioning temperature and holding time was investigated. The microstructure was analysed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is shown that the microstructure of Q&P steel is carbon-depleted lath martensite and carbon enriched retained austenite. The retained austenite appear film-type between the laths. Higher partitioning temperature and longer partitioning time can obtain more retained austenite. It is shown that with increasing partitioning time ultimate tensile strength decreases, while elongation increases obviously. Carbon-enriched metastable retained austenite is considered beneficial because the TRIP phenomenon during deformation can contribute to formability and energy absorption.

Temperature and Stress State Influence on Mechanical Properties and Damage Evolution of Dual-Phase Steels

2014 ◽  
Vol 783-786 ◽  
pp. 886-891
Author(s):  
Mayerling Martinez ◽  
Jerôme Chottin ◽  
Eric Hug
Keyword(s):  
Mechanical Properties ◽  
Automotive Industry ◽  
Volume Fraction ◽  
Tensile Tests ◽  
Dual Phase ◽  
Dual Phase Steels ◽  
Transmission Electron ◽  
Structural Applications ◽  
Microstructure Parameters ◽  
Evolution Of Microstructure

Dual Phase steels are increasingly selected for structural applications including parts in automotive industry because of their interesting mechanical properties and their good formability. This work presents an experimental analysis of the evolution of microstructure of a DP1000 alloy submitted to thermomechanical loadings. Monotonous tensile tests were performed at various plastic strain levels up to fracture for temperatures ranging between 25 °C and 440 °C. A strong degradation of the mechanical properties is observed for temperatures higher than 275 °C. The evolution with plastic strains and temperature of the microstructure was studied by scanning and transmission electron microscopy. Different microstructure parameters such as volume fraction of martensite and carbide precipitation were taken into account in order to understand the mechanical behavior of DP1000 steels tested in this temperature range. The microstructural observations indicate that diminution of carbon in martensite, due to its diffusion to form carbides, could partially explain the drop in mechanical properties at around 275 °C.

Effect of Heat Treatment on Microstructure and Properties of Cu-3Ti-1Al Alloy

2013 ◽  
Vol 749 ◽  
pp. 282-286
Author(s):  
Xian Hui Wang ◽  
Xiao Chun Sun ◽  
Xiao Hong Yang ◽  
Shu Hua Liang
Keyword(s):  
Heat Treatment ◽  
Solid Solution ◽  
Electrical Conductivity ◽  
Electron Microscope ◽  
Treatment Process ◽  
Intermetallic Phase ◽  
Strengthening Effect ◽  
Microstructure And Properties ◽  
Optimal Heat Treatment ◽  
Transmission Electron

The effect of heat treatment on the microstructure and properties of Cu-3Ti-1Al alloy was investigated. The microstructure was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), and the hardness and electrical conductivity were tested as well. The results showed that the hardness and electrical conductivity of Cu-3Ti-1Al alloy increased significantly after solid solution and ageing treatment. The strengthening effect of Cu-3Ti-1Al alloy was attributed to the formation of intermetallic phase such as Ti3Al and fine precipitates of coherent β-Cu4Ti. With increase of the aging time and the temperature, the precipitates became coarse and incoherent with Cu matrix, and the discontinuous precipitate β started to grow from grain boundaries toward grain interior, which decreased hardness. As the formation of Ti3Al, β-Cu3Ti and β-Cu4Ti phase can efficiently reduce Ti concentration in Cu matrix. The electrical conductivity of Cu-3Ti-1Al alloy increases. In the range of experiments, the optimal heat treatment process for Cu-3Ti-1Al alloy is solid solution at 850°C for 4h and ageing 500°C for 2h, and the hardness and electrical conductivity are 227HV and 12.3%IACS, respectively.

Mechanical Properties and Microstructure of Aluminum Alloy Al-6061 Obtained by the Liquid Forging Process

2010 ◽  
Vol 654-656 ◽  
pp. 1420-1423 ◽  
Author(s):  
Chun Wei Su ◽  
Peng Hooi Oon ◽  
Y.H. Bai ◽  
Anders W.E. Jarfors
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aluminum Alloy ◽  
Treatment Process ◽  
Forging Process ◽  
Al 6061 ◽  
Casting Alloys ◽  
Suitable Heat Treatment ◽  
Structural Applications ◽  
Wrought Aluminum

The liquid forging process has the flexibilities of casting in forming intricate profiles and features while imparting the liquid forged components with superior mechanical strength compared to similar components obtained via casting. Additionally, liquid forging requires significantly lower machine loads compared to solid forming processes. Currently, components that are formed by liquid forging are usually casting alloys of aluminum. This paper investigates the suitability of liquid forging a wrought aluminum alloy Al-6061 and the mechanical properties after forming. The proper handling of the Al-6061 alloy in its molten state is important in minimizing oxidation of its alloying elements. By maintaining the correct alloying composition of Al-6061 after liquid forging, these Al-6061 samples can subsequently undergo a suitable heat treatment process to significantly improve their yield strengths. Results show that the yield strengths of these liquid forged Al-6061 samples can be increased from about 90MPa, when they are in the as-liquid forged state, to about 275MPa after heat treatment. This improved yield strength is comparable to that of Al-6061 samples obtained by solid forming processes. As such, the liquid forging process here has been shown to be capable of forming wrought aluminum alloy components that has the potential for structural applications.

Relationship of Microstructure and Mechanical Properties in Er-Containing Aluminum Alloy

2015 ◽  
Vol 1120-1121 ◽  
pp. 1109-1114
Author(s):  
Xin Lei ◽  
Hui Huang ◽  
S.P. Wen
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aluminum Alloy ◽  
Treatment Process ◽  
Mg Alloys ◽  
The Other ◽  
Heat Treatment Process ◽  
Comprehensive Performance ◽  
Relationship Of ◽  
Al Mg Alloys

This study investigated the mechanical properties and microstructures of Er-containing Al–Mg alloys. The research found that the H114-T sheet of Er-containing Al–Mg alloys showed a relative good comprehensive performance in mechanical properties. With the special rolling and heat treatment process, this H114-T sheet showed different morphology of microstructures with the other sheets in Er-containing Al–Mg alloys. Grains in H114-T sheet performed irregular shape polygon, a number of subgrains appeared in grains, the amount of dislocations in grains decreased. H114-T sheet possessed a lot of Copper texture, this may be one of important factors influenced the mechanical properties.

Network Carbide Inheritance during Heat Treatment Process of Large Shield Machine Bearing Steel GCr15SiMn

2015 ◽  
Vol 817 ◽  
pp. 115-120 ◽  
Author(s):  
Dan Zhang ◽  
Le Yu Zhou ◽  
Chao Lei Zhang ◽  
Chao Huang ◽  
Min Zhao ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Treatment Process ◽  
Bearing Steel ◽  
Treatment Temperature ◽  
Heat Treatment Process ◽  
Soaking Time ◽  
Hot Rolled ◽  
Chinese Standard ◽  
Shield Machine ◽  
Quenching And Tempering

Network carbide inheritance during heat treatment process of large shield machine bearing steel GCr15SiMn was investigated by heat treatment experiments and quantitative metallographic. Samples with the proeutectoid cementite network thickness in the range of 0.19~0.54 μm were obtained by changing austenitizing temperature and soaking time of pearlite transformation. The results show that the network in hot rolled bar can be improved when the pre-heat treatment temperature is 950 °C. When the network thickness is above 0.40 μm, the undissolved cementite networks present in microstructures after quenching and tempering. In a Chinese standard, the network grades are 1.5 and 3.0 degree when the networks thickness are 0.40 μm and 0.54 μm, respectively. The critical network thickness that can be eliminated by heat treatment is 0.29 μm.

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