Composition and structure of the diamond/low carbon steel transition zone obtained by contact heating in vacuum at Fe–C eutectic temperature

2021 ◽  
pp. 47-59
Author(s):  
P. P. Sharin ◽  
M. P. Akimova ◽  
S. N. Makharova ◽  
S. P. Yakovleva ◽  
V. I. Popov
Keyword(s):  
Carbon Steel ◽  
Heating Temperature ◽  
Natural Diamond ◽  
Low Carbon Steel ◽  
Gradual Transition ◽  
Vacuum Furnace ◽  
Low Carbon ◽  
Cooling Mode ◽  
Metal Base ◽  
Diamond Crystals

The study covers the structure, elemental and phase composition of products formed in the contact interaction between diamond and low-carbon steel in vacuum at the Fe–C eutectic melting temperature. Cylindrical tablets made of low carbon steel with a maximum carbon content of 0.1 wt.% and natural diamond crystals in the form of a pyramid (or truncated pyramid) were used as contact pairs. The flat bases of diamond crystals were mounted on the horizontal surface of steel tablets with the load applied to the top of diamond crystals. Contact samples were sintered in a vacuum furnace at a maximum heating temperature of ~1165 °C. After holding at this temperature for 5 minutes, the furnace was turned off and the temperature in its chamber decreased in free cooling mode. Sintered diamond/steel tablet samples were studied by optical and scanning electron microscopy, X-ray diffraction analysis and Raman spectroscopy. It was found that the Fe–C eutectic melt forms in the diamond/steel tablet contact zone, a thin layer of which, when solidified, welds a diamond crystal to the steel tablet under the temperature-time heating mode specified in the experiment. Their bonding strength is such that welded samples without separation can withstand intense cyclic loads during grinding and polishing when making longitudinal sections of samples necessary for metallographic studies. It was shown that the Fe–C eutectic alloy is a gray cast iron with a ferrite-perlite metal base and lamellar graphite inclusions. The microhardness of the solidified Fe–C eutectic was ~1714 MPa. The initial steel tablet with a ferrite-perlite structure was subjected to cementation during sintering in contact with diamond. The most intensive cementation occurred in the ~110 μm thick unmelted upper layer of the steel tablet, which adjoined the Fe–C eutectic during sintering. The microhardness of this layer was ~4945 MPa. As it deepens into the steel tablet there is a gradual transition of the perlite-cementite structure to a perlite one and further to the initial ferrite-perlite microstructure inwards the steel tablet. At the same time, the microhardness changes from ~ 4945 to 1570 MPa.

scholarly journals Pengaruh Media Arang Kayu Bakau Mangrove Dan Arang Kayu Asam Pada Proses Perlakuan Carburizing Terhadap Sifat Mekanik Baja Karbon ST-37

2021 ◽  
Vol 12 (2) ◽  
pp. 30-37
Author(s):  
Rico Arifandi ◽  
Gerald Adityo Pohan
Keyword(s):  
Carbon Steel ◽  
Heating Temperature ◽  
Surface Hardness ◽  
Low Carbon Steel ◽  
Martensite Phase ◽  
Wood Charcoal ◽  
Holding Time ◽  
Low Carbon ◽  
Solid Media ◽  
The Impact

In the military field, tank is armored fighting vehicles that move using chain-shaped wheels. The tread of the tank chain is a component to tread and move so that it requires tougher properties on the surface and has ductile and tough properties on the inside and is more resistant to wear on the surface. The development of tank chain production materials is necessary for the independence of national defense and security as well as reducing dependence on imports. Imported tank chain hardness value 28 HRC or 286 HV. In this research, the objective of this research is to increase the surface hardness of the steel by carburizing the initial material, especially the low carbon steel ST-37. The carburizing treatment process is a method of adding carbon content in steel using solid media. The carbon media used were mangrove charcoal and tamarind wood charcoal using calcium carbonate (CaCO3) catalyst at a constant heating temperature of 900ºC, variations in holding time of 30 minutes, 60 minutes and 90 minutes, cooled rapidly with water media. Then performed an analysis of the effect of the type of wood charcoal on the mechanical properties of carbon steel ST-37. The results obtained will be applied to the tank chain tread production process. The results of the micro structure of martensite and the highest hardness value were found in the holding time of 60 minutes of mangrove charcoal media with the microstructure results of 63.8% martensite, 36.2% bainite and a hardness value of 453.1 HV. The highest toughness value is found in the holding time of 60 minutes of tamarind wood charcoal media with an impact price (HI) of 0.4345 J/mm2. The difference between the impact test results of tamarind charcoal media with mangroves is not too significant. The higher the martensite phase, the higher the hardness value. However, there is also a bainite phase which can increase the toughness of the steel which will be used as a tread chain production material.

Development of trimming technology for hot rolled ultra-low carbon steel

1993 ◽  
Vol 90 (7-8) ◽  
pp. 917-922
Author(s):  
Y. Matsuda ◽  
M. Nishino ◽  
J. Ikeda
Keyword(s):  
Carbon Steel ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Ultra Low Carbon Steel ◽  
Hot Rolled

The Effect of Small Defects on Fatigue Life of a Low Carbon Steel

2019 ◽  
Author(s):  
Natalia Gonçalves Torres ◽  
Vinícius Rodrigues ◽  
Edgar Mamiya
Keyword(s):  
Fatigue Life ◽  
Carbon Steel ◽  
Low Carbon Steel ◽  
Low Carbon

Estimation of Some Mechanical Properties for Similar & Dissimilar Welded Joints

2014 ◽  
Vol 2 (1) ◽  
pp. 59-76
Author(s):  
Abdullah Daie'e Assi
Keyword(s):  
Stainless Steel ◽  
Carbon Steel ◽  
Austenitic Stainless Steel ◽  
Base Metal ◽  
Welded Joints ◽  
Plate Thickness ◽  
Low Carbon Steel ◽  
Dissimilar Metals ◽  
Low Carbon ◽  
Steel Type

This research deals with the choice of the suitable filler metal to weld the similar and dissimilar metals (Low carbon steel type A516 & Austenitic stainless steel type 316L) under constant conditions such as, plate thickness (6 mm), voltage (78 v), current (120 A), straight polarity. This research deals with three major parts. The first parts Four types of electrodes were used for welding of dissimilar metals (C.St A516 And St.St 316L) two from mild steel (E7018, E6013) and other two from austenitic stainless steel (E309L, E308L) various inspection were carried out include (Visual T., X-ray T., δ- Ferrite phase T., and Microstructures T.) and mechanical testing include (tensile T., bending T. and micro hardness T.) The second parts done by used the same parameters to welding similar metals from (C.St A516) Or (St.St 316L). The third parts deals with welding of dissimilar weldments (C.St And St.St) by two processes, gas tungsten are welding (GTAW) and shielded metal are welding (SMAW).        The results indicated that the spread of carbon from low carbon steel to the welding zone in the case of welding stainless steel elect pole (E309L) led to Configuration Carbides and then high hardness the link to high values ​​compared with the base metal. In most similar weldments showed hardness of the welding area is  higher than the hardness of the base metal. The electrode (E309L) is the most suitable to welding dissimilar metals from (C.St A516 With St.St 316L). The results also showed that the method of welding (GTAW) were better than the method of welding (SMAW) in dissimilar welded joints (St.St 316L with C.St A516) in terms of irregular shape and integrity of the welding defects, as well as characterized this weldments the high-lift and resistance ductility good when using the welding conditions are similar.

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