Mechanized line for heat treatment of hot-rolled tubes 30?102

Metallurgist ◽  
1973 ◽  
Vol 17 (2) ◽  
pp. 129-130
Author(s):  
A. Ya. Zelikovich ◽  
O. A. Shcherbina ◽  
V. P. Pavlovskii ◽  
V. I. Krivosheev
2015 ◽  
Vol 817 ◽  
pp. 115-120 ◽  
Author(s):  
Dan Zhang ◽  
Le Yu Zhou ◽  
Chao Lei Zhang ◽  
Chao Huang ◽  
Min Zhao ◽  
...  

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.


2013 ◽  
Vol 401-403 ◽  
pp. 916-919
Author(s):  
Lin Lin Yuan ◽  
Jing Tao Han ◽  
Jing Liu

High sharpness, abrasion resistance, superior ductility, and processability are required in cutting tool materials application. Used 304(0Cr18Ni9) austenitic stainless steel as cladding and 440(7Cr17) martensitic stainless steel as core layer to produce excellently combined stainless steel plate by hot-rolled bonding in this investigation as well as researched various heat treatment processes. The results indicated that the core layer has high hardness and the cladding layer has tiny and uniform microstructure by the method of heating at 10501070°C for 15 minutes, water-cooling , then tempering at 200°C.


Metallurgist ◽  
2020 ◽  
Vol 64 (3-4) ◽  
pp. 322-333
Author(s):  
I. G. Rodionova ◽  
A. V. Amezhnov ◽  
D. V. Kudashov ◽  
V. V. Naumenko ◽  
D. L. D’yakonov ◽  
...  

2015 ◽  
Vol 365 ◽  
pp. 305-310 ◽  
Author(s):  
Diego Rafael Nespeque Correa ◽  
Pedro Akira Bazaglia Kuroda ◽  
M.L. Lourenço ◽  
Carlos Roberto Grandini

Titanium alloys present favorable properties to industry applications that depend on their composition and microstructure. Adding alloy elements and thermomechanical treatments can change the microstructure of titanium alloys. In this paper, Ti-15Zr alloys with different molybdenum quantities were prepared and hot-rolled, having been previously subjected to homogenizing heat treatment. The results showed that the microstructure of the alloys was sensible to heat treatment, in accordance with the theoretical prediction from the molecular orbital method.


2014 ◽  
Vol 1004-1005 ◽  
pp. 812-816
Author(s):  
Zhao Hui Zhang ◽  
Wei Ming Kong ◽  
Fu Cai Zhao

The surface of hot rolled ribbed steel bar after remained-heat-treatment process readily corrodes and rusts on store and transportation process due to falling off of the surface of its oxide layer in the steel production. By studying different cooling intensity having what effect on rebar structure, mechanical property and the thickness and component of surface oxide layer, this paper analyses the influence factor of strengthening mechanism and anti-corrosion on the surface oxide layer of hot rolled ribbed steel bars (HRB). The result indicates that there is a certain extent improvement on the bar’s yield strength and strength of extension after remained heat treatment, and that this change in large size bar is more distinct than which in small size’s. The most distinct strengthening effect happens in a temperature on cooling table about 720°C. Above 820°C —the temperature on cooling table, all metallographic structure consist of ferrite and pearlite (F+P); under 725°C, the sclerotic structure like bainite appears. With the temperature on cooling table arising, surface oxide layer thickens. In low temperature on cooling table, the sample integrates with matrix comparatively closely and has relatively better anti-corrode property.


Author(s):  
Matteo Ortolani ◽  
Ettore Anelli ◽  
Paolo Novelli ◽  
Emanuele Paravicini Bagliani

In case of a Weld On Connector’s riser using ASTM A182 F22 forged joints, high strength (SMYS of 80 ksi) steel pipes for sour service (hardness below or equal to 250 HV10) suitable for welding to the connectors are required. Welding is challenging because of the Post Weld Heat Treatment (PWHT) needed to reduce the hardness in the F22 HAZ while maintaining the required strength in the pipe. Theoretical evaluations were performed by means of metallurgical models and a potential solution was identified in grade P22-like steel (2¼ Cr - 1 Mo), with minor modifications with respect to the standard ASTM A335 and supplied in Q&T condition. A trial heat was cast and hot-rolled into pipes. After water quenching, the response to tempering was assessed by means of laboratory heat treatments and subsequent mechanical testing, together with metallurgical examination. Simulated PWHTs were also performed on Q&T material. 80 ksi grade P22 seamless pipes were finally produced and qualification involved mechanical testing before and after simulated PWHT: SMYS of 80 ksi and HV10 ≤ 250 requirements were met. The material also exhibited excellent toughness and resistance to HIC and SSC cracking.


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