Heat Treatment

2013 ◽  
pp. 271-324
Keyword(s):  
Heat Treatment ◽  
Surface Hardening ◽  
Precipitation Hardening ◽  
Temper Embrittlement ◽  
Induction Hardening ◽  
Heat Treatments ◽  
Metals And Alloys ◽  
Continuous Cooling Transformation Diagrams ◽  
Transformation Diagrams ◽  
Carbon System

Abstract This chapter discusses the processes used in manufacturing to thermally alter the properties of metals and alloys. It begins with a review of the iron-carbon system, the factors that affect hardenability, and the use of continuous cooling transformation diagrams. It then explains how various steels respond to heat treatments, such as annealing, normalizing, spheroidizing, tempering, and direct and interrupted quenching, and surface-hardening processes, such as flame and induction hardening, carburizing, nitriding, and carbonitriding. It also addresses the issue of temper embrittlement and discusses the effect of precipitation hardening on aluminum and other alloys.

scholarly journals The Influence of Post-Heat-Treatments on the Tensile Strength and Surface Hardness of Selective Laser Melted AlSi10Mg

2017 ◽  
Vol 370 ◽  
pp. 171-176 ◽  
Author(s):  
Leonhard Hitzler ◽  
Amandine Charles ◽  
Andreas Öchsner
Keyword(s):  
Heat Treatment ◽  
Tensile Strength ◽  
Precipitation Hardening ◽  
Elevated Temperatures ◽  
Surface Hardness ◽  
Heat Treatments ◽  
Age Hardening ◽  
Material Strength ◽  
Post Heat Treatment ◽  
Treatment Procedure

Recent investigations revealed major fluctuations in the material properties of selective laser melted AlSi10Mg, which corresponded with the varying precipitation-hardening state of the microstructure, caused by the differing dwell times at elevated temperatures. It was indicated that a subsequent heat treatment balances the age-hardening and results in a homogenized material strength. In order to further investigate this statement selective laser melted AlSi10Mg samples were subject to multiple post-heat-treatments. Subsequently, the surface hardness and tensile strength was determined and compared with the as-built results. The post-heat-treatment led to an arbitrary occurrence of rupture, indicating a successful homogenization, coupled with a remarkable improvement in ductility, but to the costs of a lowered tensile strength, which was highly dependent on the chosen heat-treatment procedure.

scholarly journals Short Heat Treatments for the F357 Aluminum Alloy Processed by Laser Powder Bed Fusion

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6157
Author(s):  
Matteo Vanzetti ◽  
Enrico Virgillito ◽  
Alberta Aversa ◽  
Diego Manfredi ◽  
Federica Bondioli ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Precipitation Hardening ◽  
Solution Treatment ◽  
Heat Treatments ◽  
Point Of View ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Heat Treated ◽  
Direct Aging

Conventionally processed precipitation hardening aluminum alloys are generally treated with T6 heat treatments which are time-consuming and generally optimized for conventionally processed microstructures. Alternatively, parts produced by laser powder bed fusion (L-PBF) are characterized by unique microstructures made of very fine and metastable phases. These peculiar features require specifically optimized heat treatments. This work evaluates the effects of a short T6 heat treatment on L-PBF AlSi7Mg samples. The samples underwent a solution step of 15 min at 540 °C followed by water quenching and subsequently by an artificial aging at 170 °C for 2–8 h. The heat treated samples were characterized from a microstructural and mechanical point of view and compared with both as-built and direct aging (DA) treated samples. The results show that a 15 min solution treatment at 540 °C allows the dissolution of the very fine phases obtained during the L-PBF process; the subsequent heat treatment at 170 °C for 6 h makes it possible to obtain slightly lower tensile properties compared to those of the standard T6. With respect to the DA samples, higher elongation was achieved. These results show that this heat treatment can be of great benefit for the industry.

The Effect of Heat Treatment and Mn, Cu and Cr Additions on the Structure of Ingots of Al-Mg-Si-Fe Alloys

2006 ◽  
Vol 519-521 ◽  
pp. 401-406 ◽  
Author(s):  
P.Yu. Bryantsev ◽  
V.S. Zolotorevskiy ◽  
V.K. Portnoy
Keyword(s):  
Heat Treatment ◽  
Solid Solution ◽  
Phase Transformations ◽  
Cooling Rate ◽  
Homogenization Temperature ◽  
Decomposition Of Solid Solution ◽  
Different Temperatures ◽  
Continuous Cooling Transformation Diagrams ◽  
Fe Alloys ◽  
Transformation Diagrams

Phase transformations in 6XXX alloys with Mn, Cu and Cr additions have been studied in the process of homogenization annealing at different temperatures. The continuous cooling transformation diagrams of decomposition of solid solution during the cooling of ingots from the homogenization temperature have been plotted. The effect of the cooling rate after homogenization on the properties of ingots during extrusion has been studied.

Effects of Post Weld Ageing Heat Treatments on the Microstructure of 17-4PH GTA Welded Joints

2011 ◽  
Vol 264-265 ◽  
pp. 1300-1305 ◽  
Author(s):  
Seyed Ali Asghar Akbari Mousavi ◽  
S.A. Hoseini Hosein Abad
Keyword(s):  
Heat Treatment ◽  
Stainless Steel ◽  
Weld Metal ◽  
Mechanical Strength ◽  
Base Metal ◽  
Precipitation Hardening ◽  
Solution Treatment ◽  
Heat Treatments ◽  
Operational Parameters ◽  
Before And After

The mechanical and metallurgical properties of the 630 (17-4PH) precipitation hardening stainless steel is greatly influenced by the type of applied heat treatments cycles. In order to achieve the homogenous microstructure in the weld metal and eliminate the HAZ due to producing the weak mechanical strength, and producing similar microstructures and mechanical strength in both weld and base metal, the study was conducted to find an optimum pre and post heat treatments before and after welding. The 2.2mm thick and 48mm tube diameter made of 630 stainless steel were welded under various operational parameters. The samples were subjected to pre weld solution treatment and post weld aging heat treatment. To reveal the microstructures of the welds, the optical and scanning electron microscopy of the welds carried out. The study shows that the direct ageing treatment at 6200C after welding can give rise to the best heat treatment to produce, the uniformity in the grain size, mechanical strength and hardness, between the base metal and the weld metal.

Effect of Heat Treatment on the Surfaces Topography Tested at the Cavitation Erosion from Steel 16MnCr5

2015 ◽  
Vol 1111 ◽  
pp. 85-90 ◽  
Author(s):  
Cristian Ghera ◽  
Ion Mitelea ◽  
Ilare Bordeaşu ◽  
Corneliu Marius Crăciunescu
Keyword(s):  
Heat Treatment ◽  
Surface Roughness ◽  
Surface Topography ◽  
Surface Hardening ◽  
Cavitation Erosion ◽  
Heat Treatments ◽  
Roughness Parameters ◽  
Surface Roughness Parameters ◽  
Duplex Treatment

This paper analyzes, by comparison, the changes appeared in surface topography, for 16MnCr5 steel tested at cavitation erosion, subjected to different type of the heat treatments. The purpose of research, aimed at establishing a correlation between resistance to cavitation erosions and the surface roughness parameters, for various types of heat treatment (annealing, carburizing, Duplex treatment of carburizing, followed by the surface hardening by induction). Cavitation tests were conducted on a vibrator device with piezoceramic crystals, which fully complies with the requirements imposed by the ASTM G32 - 2010. Roughness parameters were measured using a Mitutoyo apparatus.

scholarly journals Study the Effect of Diffusion Heat Treatments for Nickel Electroplating on the Surface Hardness of 7075 Aluminum Alloy

2016 ◽  
Vol 63 ◽  
pp. 13-21
Author(s):  
Fouad El Dahiye ◽  
Almohanad Makki ◽  
Mohamad Yehea Alnefawy
Keyword(s):  
Heat Treatment ◽  
Aluminum Alloy ◽  
Surface Hardening ◽  
Intermetallic Phase ◽  
Surface Hardness ◽  
Heat Treatments ◽  
Effect Of Temperature ◽  
7075 Aluminum Alloy ◽  
X Ray Diffraction ◽  
X Ray

In this research a surface hardening process by Ni coating and subsequent diffusion heat treatments was studied at 7075 Aluminum alloy. Nickel coatings with different thickness were obtained by change the coating time and current density. Heat treatments at 450 °C, 500 °C, and 550 °C for times (6, 12, 24) hours were performed in order to obtain surface hardening required of the aluminum alloy by diffusion of nickel into the substrate. The effect of temperature and diffusion time on surface hardness of Al 7075 alloy was studied. Surface hardness about 800 [HV] were achieved after heat treatment at 500 °C for 24 hour by diffusion of Ni in the substrate and cause of formation of Al3Ni2intermetallic phase, as x-ray diffraction tests of samples showed. While is about 670 [HV] after heat treatment at 550 °C for 24 hour because of diffusion of aluminum toward the surface of sample, as x-ray diffraction tests of samples showed.

Microstructural Development in Nb-Ti Multifilamentary Superconductors During Processing

1985 ◽  
Vol 43 ◽  
pp. 190-191
Author(s):  
A. W. West
Keyword(s):  
Heat Treatment ◽  
Critical Current Density ◽  
Copper Matrix ◽  
Wire Drawing ◽  
Heat Treatments ◽  
Microstructural Development ◽  
Final Size ◽  
Density Values ◽  
The Wire ◽  
Multifilamentary Superconductors

The influence of the filament microstructure on the critical current density values, Jc, of Nb-Ti multifilamentary superconducting composites has been well documented. However the development of these microstructures during composite processing is still under investigation.During manufacture, the multifilamentary composite is given several heat treatments interspersed in the wire-drawing schedule. Typically, these heat treatments are for 5 to 80 hours at temperatures between 523 and 573K. A short heat treatment of approximately 3 hours at 573K is usually given to the wire at final size. Originally this heat treatment was given to soften the copper matrix, but recent work has shown that it can markedly change both the Jc value and microstructure of the composite.

REPUBLIC 65

Alloy Digest ◽  
1960 ◽  
Vol 9 (5) ◽  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Tensile Properties ◽  
Yield Point ◽  
Precipitation Hardening ◽  
Heat Treating ◽  
Low Alloy Steel ◽  
Rolled Condition ◽  
Hardening Heat Treatment ◽  
Minimum Yield

Abstract REPUBLIC-65 is a precipitation hardenable low alloy steel which will meet 65000 psi minimum yield point in the as-rolled condition followed by a precipitation hardening heat treatment. This datasheet provides information on composition, hardness, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-98. Producer or source: Republic Steel Corporation.

Quantitative Microstructural Analysis of a Ni-based Superalloy After Different Heat Treatments

2020 ◽  
Vol 70 (12) ◽  
pp. 4519-4524
Keyword(s):  
Heat Treatment ◽  
Internal Structure ◽  
Microstructural Analysis ◽  
Temperature Treatment ◽  
Heat Treatments ◽  
Metal Melts ◽  
Metallic Inclusions ◽  
Undercooled Melt ◽  
Super Alloy

The efficiency of time-temperature treatment (T-TT) on metal melts can be microstructurally analysed through their degree of purity in non-metallic inclusions. In the case of the Ni-based super alloy under discussion (MSRR 7045) the heat treatment was the undercooling consequences both on the durability of the casting environment (ingots-refractories) and on the internal structure of the metal (porosity, microstructural isotropy). Keywords: time-temperature treatment, undercooled melt, non-metallic inclusions, purity, microstructural isotropy

scholarly journals Influence of Deep Rolling and Induction Hardening on Microstructure Evolution of Crankshaft Sections made from 38MnSiVS5 and 42CrMo4

2021 ◽  
Vol 76 (3) ◽  
pp. 175-194
Author(s):  
A. Fischer ◽  
B. Scholtes ◽  
T. Niendorf
Keyword(s):  
Process Parameters ◽  
Microstructure Evolution ◽  
Surface Hardening ◽  
Qualitative Evaluation ◽  
Induction Hardening ◽  
Deep Rolling ◽  
Automotive Components ◽  
Hardening Treatment ◽  
Steel Grades ◽  
Definition Of

Abstract In order to improve properties of complex automotive components, such as crankshafts, in an application-oriented way, several surface hardening treatments can be applied. Concerning the material performance the definition of adequate process parameters influences the resulting surface properties and, thus, the effectiveness of surface hardening treatments. To analyze most relevant process-microstructure-property relationships, the present paper reports results obtained by two different well-established surface hardening procedures, i. e. deep rolling as a mechanical treatment and induction hardening as a thermal treatment. For each hardening process widely used crankshaft steel grades, i. e. a medium carbon 38MnSiVS5 microalloyed steel and a quenched and tempered 42CrMo4 were selected and thoroughly characterized upon processing, using equal parameter settings. The results reveal that deep rolling in contrast to induction hardening proves to be a less sensitive surface layer treatment with regard to small differences in the initial microstructure, the chemical composition and the applied process parameters. Differences in microstructure evolution with respect to the applied surface hardening treatment are studied and discussed for the highly stressed fillet region of automotive crankshaft sections for all conditions. In this context, high-resolution SEM-based techniques such as EBSD and ECCI are proven to be very effective for fast qualitative evaluation of induced microstructural changes.

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