scholarly journals Investigation of Micromechanical Properties and Tribological Behavior of WE43 Magnesium Alloy after Deep Cryogenic Treatment Combined with Precipitation Hardening

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7343
Author(s):  
Adrian Barylski ◽  
Krzysztof Aniołek ◽  
Grzegorz Dercz ◽  
Piotr Kowalewski ◽  
Sławomir Kaptacz ◽  
...  
Keyword(s):  
Precipitation Hardening ◽  
Tribological Behavior ◽  
Cryogenic Treatment ◽  
Linear Wear ◽  
Volumetric Wear ◽  
Deep Cryogenic Treatment ◽  
The Coefficient Of Friction ◽  
We43 Magnesium Alloy ◽  
Zr Alloy ◽  
We43 Alloy

This study investigated the micromechanical and tribological properties of WE43 alloy (Mg-Y-Nd-Zr) alloy subjected to cryogenic treatment and precipitation hardening. Microindentation tests were carried out in the range of load from 100 to 1000 mN. The introduction of deep cryogenic treatment (DCT) was shown to increase hardness and Young’s modulus, and reduce the total indentation work. As the load set during the tests increased, a gradual decrease in the measured values was observed, indicating a significant relationship between the indent size and the value of the measured parameters. Cryogenic treatment used in conjunction with precipitation hardening (after solutioning and after aging) reduces the tribological wear of the alloy. Tests have shown an almost twofold reduction in the area of the wear trace and in the volumetric wear of the alloy, as well as a more than twofold reduction in linear wear, with relatively small fluctuations in the coefficient of friction. Abrasion was the main mechanism of wear. Areas where microcutting, adhesion and plastic deformation occurred were also observed. The results indicate the significant effectiveness of the applied heat treatment in improving the service life of the WE43 alloy containing rare earth metals.

Studies on Cryogenic Treated Drills Under Nano-Fluid Based Reduced Quantity Lubrication Conditions for Machining Ti6Al4V

2018 ◽  
Author(s):  
D. Samuel Raj ◽  
Jerome Arul Praveen C. ◽  
Aarthi S. Kumaran
Keyword(s):  
Tool Wear ◽  
Cryogenic Treatment ◽  
Minimum Quantity Lubrication ◽  
Nano Particles ◽  
Limiting Factors ◽  
Cutting Fluids ◽  
Deep Cryogenic Treatment ◽  
Nano Fluid ◽  
The Coefficient Of Friction ◽  
Marginal Improvement

Minimum quantity lubrication (MQL) machining is gaining wide acceptance because of the need to make machining more environment friendly. With cutting fluids contributing more than 10–15% of the manufacturing costs, economics of MQL is also gaining interest. The initial cost of commercial MQL systems is one of the limiting factors hindering their adoption in small and medium scale industries. This study, uses a simple commercial paint sprayer with a portable compressor (with a total cost < $125) to produce an MQL like spray with a slightly higher flow rate as compared to MQL (and is thus called reduced quantity lubrication) in drilling Ti6Al4V. Tungsten carbide drills of 7 mm diameter were subjected to deep cryogenic treatment, which has been acknowledged as a means of improving tool wear resistance. There was a marginal improvement in drill microhardness as a result of cryogenic treatment. The performance of untreated and cryo-treated drills was compared for tool wear, hole surface roughness and cutting forces. In addition to the normal air-coolant mist, the effect of adding nano-particles in the coolant was also studied. It is found that cryo-treated drills under nano-fluid based reduced quantity lubrication (RQL) conditions performed better than untreated drills and conventional cutting fluids, in terms of all the three measured parameters. This can be attributed to the higher thermal conductivity of nano-fluid based coolants and their ability to reduce the coefficient of friction at the chip-tool interface.

scholarly journals The Sclerometrical, Mechanical, and Wear Behavior of Mg-Y-Nd Magnesium Alloy after Deep Cryogenic Treatment Combined with Heat Treatment

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1218
Author(s):  
Adrian Barylski ◽  
Krzysztof Aniołek ◽  
Grzegorz Dercz ◽  
Marian Kupka ◽  
Izabela Matuła ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Abrasive Wear ◽  
Precipitation Hardening ◽  
Wear Behavior ◽  
Cryogenic Treatment ◽  
Solution Treatment ◽  
Precipitation Process ◽  
Deep Cryogenic Treatment ◽  
Β Phase ◽  
Fold Reduction

The paper investigates changes in the structure, microhardness, and sclerometrical and tribological properties of a Mg-Y-Nd alloy under the influence of deep cryogenic treatment (DCT) in combination with heat treatment. The solution treatment was carried out at 545 °C for 8 h, aging was carried out at 250 °C for 24 h, and the deep cryogenic treatment applied at different treatment stages was performed at −196 °C. Tests showed a significant increase in the number of β-phase precipitates identified as Mg46.1Y6.25RE3.45 in the alloy subjected to DCT after solution treatment followed by aging. In addition, an approximately 20% reduction of the grain size was observed. Changes in the structure in the precipitation process strengthened the alloy and resulted in an increase of its hardness. At the same time, sclerometric tests allowed the micromechanism of wear and the coefficient of resistance to abrasive wear to be determined. Tribological tests showed a three-fold reduction in the volumetric wear and a considerable reduction of the friction coefficient, with the main mechanism observed during friction being abrasive wear. The most favorable properties of the alloy were obtained after precipitation hardening combined with DCT, resulting in a large increase in resistance to abrasive wear. Additionally, the formation of deep scratches in the examined material was reduced. The introduction of sub-zero treatment reduces the precipitation hardening time, and the results obtained indicate that the service life of the Mg-Y-Nd alloy can be extended.

scholarly journals Effect of deep cryogenic treatment on surface chemistry and microstructure of selected high-speed steels

2021 ◽  
Vol 548 ◽  
pp. 149257
Author(s):  
Patricia Jovičević-Klug ◽  
Monika Jenko ◽  
Matic Jovičević-Klug ◽  
Barbara Šetina Batič ◽  
Janez Kovač ◽  
...  
Keyword(s):  
Surface Chemistry ◽  
High Speed ◽  
Cryogenic Treatment ◽  
Deep Cryogenic Treatment

Effects of deep cryogenic treatment on machinability, hardness and microstructure in dry turning process of tempered steels

2020 ◽  
pp. 095440892097944
Author(s):  
Menderes Kam
Keyword(s):  
Cryogenic Treatment ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Point Of View ◽  
Turning Process ◽  
Deep Cryogenic Treatment ◽  
Dry Turning ◽  
Control Factors ◽  
Heat Treated ◽  
Hardness Values

This study investigated the effects of Deep Cryogenic Treatment (DCT) on machinability, hardness, and microstructure in dry turning process of AISI 4140 (48-51 HRc) tempered steels with ceramic cutting tools on the surface roughness (Ra). DCT process of steels has shown significant improvement in their mechanical properties. In this context, experiments were made with Taguchi L16 method and optimum values were determined. Three different values for each control factors as: different heat treated samples, cutting speeds (160, 200, 240, 280 m/min), feed rates (0.08, 0.12, 0.16, 0.20 mm/rev) were selected. As a result, the lowest Ra value was found to be 0.159 µm for the DCTT36 sample at a cutting speed of 240 m/min, a feed rate of 0.08 mm/rev. The optimum Ra value was the lowest for the DCTT36 sample compared to the other samples as 0.206 µm. The hardness values of the micro and macro were highest for the DCTT36 sample. Microstructural point of view Scanning Electron Microscopy (SEM) point of view, the DCCT36 sample showed that best results owing to its homogeneity. It was concluded that lower Ra values can be obtained with ceramic cutting tool in dry turning experiments according to the studies in the literature review. It is thought to be preferred as an alternative to cylindrical grinding process due to lower cost.

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