Austenite phase transformation of SKD11 by surface heat treatment with a focused electron beam

2017 ◽  
Vol 321 ◽  
pp. 247-256 ◽  
Author(s):  
Eun Goo Kang ◽  
Honzong Choi ◽  
Byung-Kwon Min ◽  
Sang Jo Lee
2019 ◽  
Vol 34 ◽  
pp. 10-17
Author(s):  
Adriana Zara ◽  
Maria Stoicănescu ◽  
I. Giacomelli

Usage of electron beam shows the possibility of using its energy in different thermic processes. Among these, it is found the heating of mechanical products for the surface heat treatment. During the effectuated practical attempts, two types of construction steels were analyzed, namely carbon steel (OLC 45) and a low alloyed steel (41 Cr 4). The electron beam was applied on samples that were previous subjected to the heat treatment of improvement. The working parameters were chosen in order to obtain the heating of the superficial layer without melting. The samples treated as above were subjected to studies regarding the metallographic structures and the resulted hardness; also there were effectuated wear attempts. It was concluded that the use of electron beam in superficial heat treatment may also fit in practical terms.


1992 ◽  
Vol 7 (11) ◽  
pp. 3065-3071 ◽  
Author(s):  
Peir-Yung Chu ◽  
Isabelle Campion ◽  
Relva C. Buchanan

Phase transformation and preferred orientation in ZrO2 thin films, deposited on Si(111) and Si(100) substrates, and prepared by heat treatment from carboxylate solution precursors were investigated. The deposited films were amorphous below 450 °C, transforming gradually to the tetragonal and monoclinic phases on heating. The monoclinic phase developed from the tetragonal phase displacively, and exhibited a strong (111) preferred orientation at temperature as low as 550 °C. The degree of preferred orientation and the tetragonal-to-monoclinic phase transformation were controlled by heating rate, soak temperature, and time. Interfacial diffusion into the film from the Si substrate was negligible at 700 °C and became significant only at 900 °C, but for films thicker than 0.5 μm, overall preferred orientation exceeded 90%.


Author(s):  
Abhijit Biswas ◽  
Suman Kalyan Das ◽  
Prasanta Sahoo

The microstructural changes of electroless Ni–P–Cu coating at various heat-treatment conditions are investigated to understand its implications on the tribological behavior of the coating. Coatings are heat-treated at temperatures ranging between 200°C and 800 °C and for 1–4 h duration. Ni–P–Cu coatings exhibit two-phase transformations in the temperature range of 350–450 °C and the resulting microstructural changes are found to significantly affect their thermal stability and tribological attributes. Hardness of the coating doubles when heat-treated at 452 °C, due to the formation of harder Ni3P phase and crystalline NiCu. Better friction and wear performance are also noted upon heat treatment of the coating at the phase transformation regime, particularly at 400 °C. Wear mechanism is characterized by a mixed adhesive cum abrasive wear phenomena. Heat treatment at higher temperature (600 °C and above) and longer duration (4 h) results in grain coarsening phenomenon, which negatively influences the hardness and tribological characteristics of the coating. Besides, diffusion of iron from the ferrous substrate as well as greater oxide formation are noticed when the coating is heat-treated at higher temperatures and for longer durations (4 h).


Sign in / Sign up

Export Citation Format

Share Document