Surface alloying of alloy AL25 by laser

1988 ◽  
Vol 30 (5) ◽  
pp. 348-350
Author(s):  
I. V. Bogolyubova ◽  
I. F. Deriglazova ◽  
B. F. Mul'chenko
Keyword(s):  
Author(s):  
P. A. Molian ◽  
K. H. Khan ◽  
W. E. Wood

In recent years, the effects of chromium on the transformation characteristics of pure iron and the structures produced thereby have been extensively studied as a function of cooling rate. In this paper, we present TEM observations made on specimens of Fe-10% Cr and Fe-20% Cr alloys produced through laser surface alloying process with an estimated cooling rate of 8.8 x 104°C/sec. These two chromium levels were selected in order to study their phase transformation characteristics which are dissimilar in the two cases as predicted by the constitution diagram. Pure iron (C<0.01%, Si<0.01%, Mn<0.01%, S=0.003%, P=0.008%) was electrodeposited with chromium to the thicknesses of 40 and 70μm and then vacuum degassed at 400°F to remove the hydrogen formed during electroplating. Laser surface alloying of chromium into the iron substrate was then performed employing a continuous wave CO2 laser operated at an incident power of 1200 watts. The laser beam, defocussed to a spot diameter of 0.25mm, scanned the material surface at a rate of 30mm/sec, (70 ipm).


Author(s):  
N. Pirch ◽  
G. Backes ◽  
E. W. Kreutz ◽  
X. He ◽  
A. Weisheit ◽  
...  

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1246
Author(s):  
Stefan Valkov ◽  
Dimitar Dechev ◽  
Nikolay Ivanov ◽  
Ruslan Bezdushnyi ◽  
Maria Ormanova ◽  
...  

In this study, we present the results of Young’s modulus and coefficient of friction (COF) of Ti–Ta surface alloys formed by electron-beam surface alloying by a scanning electron beam. Ta films were deposited on the top of Ti substrates, and the specimens were then electron-beam surface alloyed, where the beam power was varied from 750 to 1750 W. The structure of the samples was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Young’s modulus was studied by a nanoindentation test. The coefficient of friction was studied by a micromechanical wear experiment. It was found that at 750 W, the Ta film remained undissolved on the top of the Ti, and no alloyed zone was observed. By an increase in the beam power to 1250 and 1750 W, a distinguished alloyed zone is formed, where it is much thicker in the case of 1750 W. The structure of the obtained surface alloys is in the form of double-phase α’and β. In both surface alloys formed by a beam power of 1250 and 1750 W, respectively, Young’s modulus decreases about two times due to different reasons: in the case of alloying by 1250 W, the observed drop is attributed to the larger amount of the β phase, while at 1750 W is it due to the weaker binding forces between the atoms. The results obtained for the COF show that the formation of the Ti–Ta surface alloy on the top of Ti substrate leads to a decrease in the coefficient of friction, where the effect is more pronounced in the case of the formation of Ti–Ta surface alloys by a beam power of 1250 W.


2019 ◽  
Vol 784 ◽  
pp. 1106-1112 ◽  
Author(s):  
Ke Chen ◽  
Lingguo Zeng ◽  
Zhijun Li ◽  
Linjiang Chai ◽  
Yueyuan Wang ◽  
...  

2004 ◽  
Vol 551 (1-2) ◽  
pp. 9-22 ◽  
Author(s):  
Adrián Canzian ◽  
Hugo O Mosca ◽  
Guillermo Bozzolo
Keyword(s):  

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