Processing and characterization of high strength dual-phase steel by two-step intercritical heat treatment process

2018 ◽  
Vol 233 (3) ◽  
pp. 581-588 ◽  
Author(s):  
Praveen Singh ◽  
Satnam Singh ◽  
Sanchit Mewar
Keyword(s):  
Heat Treatment ◽  
Tensile Strength ◽  
Treatment Process ◽  
Heat Treatment Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Treated Steel ◽  
Heat Treated ◽  
Intercritical Heat Treatment ◽  
Heat Treated Steel

A simple approach of two-step intercritical heat treatment has been employed to study the effect of heat treatment on the evolution of microstructures and their effect on the mechanical properties of alloy steel (AISI 1012). The selected steel samples were directly placed in the preheated furnace and were progressively heat treated in two steps, intercritically between the Ac1–Ac3 temperature range. Immediate water quenching (preheated at 30 ℃) was carried out after heat treatment cycles. The processed steels were characterized by examining the X-ray diffraction patterns, microstructures, Vickers microhardness, and tensile strength. The normalized X-ray diffraction results of heat-treated steels revealed the substantial growth in the martenistic phases. The microstructures of heat-treated steel revealed the formation of needle-shape-like structures, which corresponds to the martenistic phase. The increased formation of martenistic phase due to the intercritical heat treatment process improved the overall microhardness (from 188 ± 9 HV of the parent steel to 412 ± 32 HV for 800 ℃ heat-treated steel) up to 2.2 times. The presence of soft and ductile (ferritic and pearlite) phases simultaneously with tough and strong (martenistic) phase allowed the improvement in the ultimate tensile strength. In comparison to parent steel with tensile strength of 510 ± 15 MPa, the intercritical heat treatment steel at 800 ℃ revealed 169.6% higher tensile strength of 1375 ± 35 MPa. However, percentage elongation was reduced by 60%, i.e. from 13 ± 1% for parent steel to 5.2 ± 2% of intercritical heat treatment steel (processed at 800 ℃). An overall study revealed that by a proper intercritical heat treatment process, dual-phase steels with better structure–properties correlation can be obtained for industrial applications.

High Tensile Strength of Drawn Gold

2005 ◽  
Vol 495-497 ◽  
pp. 907-912 ◽  
Author(s):  
Suk Hoon Kang ◽  
Hee Suk Jung ◽  
Woong Ho Bang ◽  
Jae Hyung Cho ◽  
Kyu Hwan Oh ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Tensile Strength ◽  
Treatment Process ◽  
Gold Wire ◽  
Equivalent Strain ◽  
Heat Treatment Process ◽  
High Tensile Strength ◽  
Heat Treated ◽  
Gold Wires

This paper studies the microstructure of drawn gold wires to equivalent strain of 10 and to equivalent strain of 8.5 then heat-treated. The texture of gold wire drawn to strain of 10 is mainly composed of <100> and <111> fibers. Tensile strength of the gold wire increases with <111> fiber fraction, while the grain size does not appear to affect the tensile property. With an exception at heat treatment at 600oC, the texture of gold wire drawn the strain of 8.5 is replaced with <100> fiber component by heat treatment process at 400~700oC. Heat treatment at 600oC produces <110> fiber or <112> fiber, depending upon annealing time.

Hydroxyapatite Extracted from Fish Bone Wastes by Heat Treatment

2020 ◽  
Vol 840 ◽  
pp. 318-323
Author(s):  
Hestining Ajeng Permatasari ◽  
Rosita Wati ◽  
Rista Mutia Anggraini ◽  
Almukarramah Almukarramah ◽  
Yusril Yusuf
Keyword(s):  
Heat Treatment ◽  
Treatment Process ◽  
Low Cost ◽  
Xrd Analysis ◽  
Fish Bone ◽  
Heat Treatment Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Edx Analysis ◽  
Fish Bones

The present work demonstrates a low-cost route to produce hydroxyapatite (HAp) from fish bones (natural source) by a simple heat-treatment process. The produced HAp was characterized by X-ray Diffraction (XRD) and Fourier Transform Infra-Red (FTIR). Energy Dispersive X-ray (EDX) analysis obtained elemental composition that confirmed the presence of Ca and P; then the Ca/P mole ratio was calculated. XRD analysis from Chanos chanos and Calarias batracus bone has produced the diffraction peaks at 31.8°, 32.1°, and 32.9° that corresponded to the HAp phase. The presence of functional groups, PO43‒ and OH‒, has been confirmed by FTIR spectra that arecharacteristics of HAp. EDX analysis has shown that the Ca/P mole ratio was similar to the Ca/P mole ratio of the HAp’s stoichiometry (1.66). But actually, not all fish bones can produce pure HAp after the heat-treatment process, such as Tylosurus crocodilus bone. Based on XRD analysis from the main diffraction peak form is a β-TCP phase

Hardening of Selective Laser Melted M2 Steel

2021 ◽  
Author(s):  
Mei Yang ◽  
Yishu Zhang ◽  
Haoxing You ◽  
Richard Smith ◽  
Richard D. Sisson
Keyword(s):  
Heat Treatment ◽  
High Speed ◽  
Cutting Tools ◽  
High Speed Steel ◽  
High Hardness ◽  
Steel Part ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Near Net Shape

Abstract Selective laser melting (SLM) is an additive manufacturing technique that can be used to make the near-net-shape metal parts. M2 is a high-speed steel widely used in cutting tools, which is due to its high hardness of this steel. Conventionally, the hardening heat treatment process, including quenching and tempering, is conducted to achieve the high hardness for M2 wrought parts. It was debated if the hardening is needed for additively manufactured M2 parts. In the present work, the M2 steel part is fabricated by SLM. It is found that the hardness of as-fabricated M2 SLM parts is much lower than the hardened M2 wrought parts. The characterization was conducted including X-ray diffraction (XRD), optical microscopy, Scanning Electron Microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) to investigate the microstructure evolution of as-fabricated, quenched, and tempered M2 SLM part. The M2 wrought part was heat-treated simultaneously with the SLM part for comparison. It was found the hardness of M2 SLM part after heat treatment is increased and comparable to the wrought part. Both quenched and tempered M2 SLM and wrought parts have the same microstructure, while the size of the carbides in the wrought part is larger than that in the SLM part.

EFFECT OF HEAT TREATMENT ON MICROSTRUCTURE AND CORROSION RESISTANCE OF Ni-B-W-Mo COATING DEPOSITED BY ELECTROLESS METHOD

2018 ◽  
Vol 25 (08) ◽  
pp. 1950023 ◽  
Author(s):  
ARKADEB MUKHOPADHYAY ◽  
TAPAN KUMAR BARMAN ◽  
PRASANTA SAHOO
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Electrochemical Techniques ◽  
Sodium Molybdate ◽  
Medium Carbon Steel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid Solution Strengthening ◽  
Heat Treated ◽  
Electroless Coatings

The present work reports the deposition of a quaternary Ni-B-W-Mo coating on AISI 1040 medium carbon steel and its characterization. Quaternary deposits are obtained by suitably modifying existing electroless Ni-B bath. Composition of the as-deposited coating is analyzed by energy dispersive X-ray spectroscopy. The structural aspects of the as-deposited and coatings heat treated at 300[Formula: see text]C, 350[Formula: see text]C, 400[Formula: see text]C, 450[Formula: see text]C and 500[Formula: see text]C are determined using X-ray diffraction technique. Surface of the as-deposited and heat-treated coatings is examined using a scanning electron microscope. Very high W deposition could be observed when sodium molybdate is present in the borohydride-based bath along with sodium tungstate. The coatings in their as-deposited condition are amorphous while crystallization takes place on heat treatment. A nodulated surface morphology of the deposits is also observed. Vickers’ microhardness and crystallite size measurement reveal inclusion of W and Mo results in enhanced thermal stability of the coatings. Solid solution strengthening of the electroless coatings by W and Mo is also observed. The applicability of kinetic strength theory to the hardening of the coatings on heat treatment is also investigated. Corrosion resistance of Ni-B-W-Mo coatings and effect of heat treatment on the same are also determined by electrochemical techniques.

scholarly journals Preparation and Assessment of Heat-Treated α-Chitin Nanowhiskers Reinforced Poly(viny alcohol) Film for Packaging Application

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1883 ◽  
Author(s):  
Chao Peng ◽  
Guangxue Chen
Keyword(s):  
Heat Treatment ◽  
Composite Films ◽  
Barrier Properties ◽  
Mechanical Tests ◽  
Light Transmittance ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Chitin Nanowhiskers

In this study, poly(vinyl alcohol) (PVA) composite films enhanced by α-chitin nanowhiskers (ChWs) were prepared through heat treatment. The obtained membranes were assessed by means of FTIR spectroscopy, X-ray diffraction, thermogravimetric analysis, regular light transmittance, mechanical tests, permeability and water absorption. The influence of the nano-component and heat treatment on the mechanical, thermal and water-resistant properties of the composite membrane were analyzed. From the results of the work, the produced films with excellent barrier properties and inexpensive raw processed materials have great prospects in packaging applications.

Magnetization and XRD Studies of Laser Heat Treated SmCo5 Powders

2021 ◽  
Vol 1016 ◽  
pp. 1299-1304
Author(s):  
Naidu Seetala ◽  
Deidre Henderson ◽  
Jumel Jno-Baptiste ◽  
Hao Wen ◽  
Sheng Min Guo
Keyword(s):  
Heat Treatment ◽  
Hydrogen Gas ◽  
Vacuum Furnace ◽  
X Ray Diffraction ◽  
X Ray ◽  
Micro Particles ◽  
Laser Heat ◽  
Heat Treated ◽  
Xrd Studies ◽  
Hydride Phases

The microstructure and magnetization of SmCo5 micro-particles may be used as feedstock for 3D printing to make miniature strong magnets. Thus, the magnetic response and microstructures of commercially available SmCo5 micro-particles were studied under various heat treatments using a high wattage laser. The magnetization of laser heat treated powders at 50-watt showed an increase in magnetization, while the 75-watt melt showed a little to no change. Unfortunately, the coercivity of both laser heat treated samples decreased significantly. Oxidation during the heat treatment is suspected to result in low coercivity. Purging with argon-gas prior to laser heating showed improved coercivity. To further minimize the oxidation problem a set of SmCo5 powder was reduced prior to laser heat treatment using a constant flow of hydrogen gas while being heated at various temperatures from 100 oC to 400 oC for a period of ~4 hours. The results show that the magnetization generally increases with the temperature, while the coercivity decreases significantly. Another set of SmCo5 was annealed in a vacuum furnace for one hour at temperatures between 200 oC and 400 oC in order to confirm that no hydride phases were formed during reduction. The magnetization and coercivity showed similar variations with annealing temperature to those for the reduced powders confirming that these variations may be due to change in crystal structure rather than formation of hydrides. X-ray Diffraction (XRD) studies were performed to identify the changes in crystal phases.

THE NEW HEAT TREATMENT TECHNOLOGY OF A356 ALUMINIUM ALLOY PREPARED BY PTC

2009 ◽  
Vol 23 (06n07) ◽  
pp. 906-913 ◽  
Author(s):  
LIANYONG ZHANG ◽  
YANHUA JIANG ◽  
ZHUANG MA ◽  
WENKUI WANG
Keyword(s):  
Electron Microscopy ◽  
Phase Transition ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Treatment Process ◽  
A356 Alloy ◽  
Heat Treatment Process ◽  
X Rays ◽  
Treatment Technology ◽  
Conventional Heat Treatment

Phase Transition Cooling (PTC), using the absorbed latent heat during the melting of phase transition cooling medium to cool and solidify alloys in the process of casting, is a new casting technology. Specimens of A356 casting aluminum alloy were prepared by this method in the paper. The new heat treatment process (cast and then aging directly without solid solution) of A356 alloy was performed. For comparison, the conventional T6 heat treatment (solution and then aging treatment) was performed too. The mechanical properties of A356 alloy with different heat treatments were measured by tensile strength testing methods and microstructures of the alloy with different heat treatment process were investigated by optical microscopy (OM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-rays diffraction (XRD) and transmission electron microscopy (TEM) too. The results show that ultimate tensile strength (UTS) of A356 alloy with the new heat treatment process is much higher than that with conventional heat treatment while the elongations with the two heat treatment processes are very close. This is due to the grain refinement obtained after PTC processing.

Copper(I) Halide Nanoparticle-dispersed Glasses Prepared by Copper Staining

2005 ◽  
Vol 20 (9) ◽  
pp. 2480-2485 ◽  
Author(s):  
Kohei Kadono ◽  
Tatsuya Suetsugu ◽  
Takeshi Ohtani ◽  
Toshihiko Einishi ◽  
Takashi Tarumi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Surface Region ◽  
Borosilicate Glasses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Depth Profiles ◽  
Transmission Electron ◽  
Heat Treated ◽  
Glass Heat

Copper(I) chloride and bromide nanoparticle-dispersed glasses were prepared by means of a conventional copper staining. The staining was performed by the following process: copper stain was applied on the surfaces of Cl−- or Br−-ion-containing borosilicate glasses, and the glasses were heat-treated at 510 °C for various times. Typical exciton bands observed in the absorption spectra of the glasses after the heat treatment indicated that CuCl and CuBr particles were formed in the surface region of the glasses. The average sizes of the CuCl and CuBr particles in the glasses heat-treated for 48 h were estimated at 4.8 and 2.7 nm, respectively. The nanoparticles were also characterized by x-ray diffraction and transmission electron microscopy. Depth profiles of Cu and CuBr concentration in the glass heat-treated for 48 h were measured. Copper decreased in concentration monotonously with depth, reaching up to 60 μm, while the CuBr concentration had a maximum at about 25 μm in depth.

Nanostructured YSZ Thin Film for Application as Electrolyte in an Electrode Supported SOFC

2012 ◽  
Vol 727-728 ◽  
pp. 873-878
Author(s):  
Cibele Melo Halmenschlager ◽  
Matias de Angelis Korb ◽  
Roberto Neagu ◽  
Carlos Pérez Bergmann ◽  
Célia de Fraga Malfatti
Keyword(s):  
Thin Film ◽  
Heat Treatment ◽  
Treatment Process ◽  
Precursor Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Influence ◽  
Different Temperatures ◽  
Spray Pyrolysis Process ◽  
Fast Increase

The development of solid oxide fuel cell with thin film concepts for an electrode supported design based on the yttria-stabilized zirconia has demonstrated favourable results due to its high chemistry stability in oxidization and environment reduction. The spray pyrolysis process was investigated in order to obtain dense thin films of YSZ on different substrates. The precursor solution was obtained by zirconium and yttrium salt dissolutions in a mixture of water and glycerine in several ratios to study the solvent influence. The substrate was initially heated at 600 °C and during the deposition it ranged from 260-350°C, finishing at a fast increase in temperature of 600°C. The heat treatment was carried out in four different temperatures: 700 °C, 750 °C, 800 °C, and 900 °. The precursors were characterized by thermal analysis. The microstructures of the films were studied using scanning electron microscopy and X-ray diffraction. The results obtained showed that the films obtained were crystalline before the heat treatment process and have shown ionic conductivity above 800°C.

Effects of Heat Treatment on the Mechanical and Tribological Properties of Aluminium (LM6) Reinforced with Iron Oxide (Fe2O3)

2020 ◽  
Vol 12 (3) ◽  
Author(s):  
J. Arun Prakash ◽  
P. Shanmughasundaram ◽  
M. Vemburaj ◽  
P. Gowtham
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Iron Oxide ◽  
Treatment Process ◽  
Casting Process ◽  
Stir Casting ◽  
Heat Treatment Process ◽  
Treatment Results ◽  
Mechanical And Tribological Properties

This work deals with the examination of the mechanical properties of Aluminium (LM6) reinforced with iron oxide (Fe2O3). Stir casting process is used to formulate the composite sampling by varying iron oxide in 5% and 10% by weight. Three different heat treatment process of hardening, annealing and normalizing is carried out on samples of aluminium (LM6), aluminium (LM6) + 5% Fe2O3 and aluminium (LM6) + 10% Fe2O3. Composite specimens are tested to analyze the mechanical properties such as hardness, yield stress, tensile strength and elongation. Present reinforcement specks enabled the alloy to preserve higher hardness during the heat treatment. Results have shown substantial improvements in properties of the specimens with various compositions of reinforcement.

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