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Open Access Article
1 - Measurement of dielectric loss tangent at cryogenic temperature using superconducting film resonator
Yufang Zhang Zhenqing Wang -
Open Access Article
2 - The Effect of Cooling Rate on the Microstructure and Mechanical Properties of the Plastic Injection Molds
Z. S Seyedraoufi M Samiee F Abdi -
Open Access Article
3 - Thermal Loads and Surface Quality Evaluation in Machining of Hardened Die Steel under Dry and Cryogenic Machining
Farshid Jafarian Emad Mohseni -
Open Access Article
4 - Investigation on High Temperature Wear Resistance of Cryotreated Hot Work Tool Steel
Iman Ebrahimzadeh Farhad Gharavi کامران امینی zahra Ghorbani -
Open Access Article
5 - Study the Effects of the Cryogenic Method Using Liquid Nitrogen on Fittings in Assembly Process
Mohammad Mesgar Ahmad Afsari Sayed Ahmad Behgozin Seyed Javad Asnaashari -
Open Access Article
6 - Evaluation of the Cryogenic Effect on Friction Stir Processed AA7075/Si Matrix Nanocomposites
Navid Molla Ramezani Behnam DavoodiFriction-stir processing is a green manufacturing process for surface composite fabrication and surface modification. To achieve this critical goal, the type of cooling and lubrication are of great importance. Therefore, in this paper, the cryogenic effects were investi MoreFriction-stir processing is a green manufacturing process for surface composite fabrication and surface modification. To achieve this critical goal, the type of cooling and lubrication are of great importance. Therefore, in this paper, the cryogenic effects were investigated on friction-stir processing (FSP) tool wear and surface quality of an aluminum matrix nanocomposite. Silicon carbide (SiC) nanopowder was used as the reinforcing phase. The effects of cooling strategy and tool rotation speed on the tool wear, microhardness, surface roughness, and energy dispersive spectroscopy (EDS) analysis were studied. The cooling procedure was conducted under dry and cryogenic conditions. Additionally, the rotation speed was set at three levels, while other parameters were kept constant. The FSP tools were examined under a scanning electron microscope, and the wear mechanisms were investigated under different conditions. The results showed that tool wear, surface roughness, and microhardness were improved under cryogenic conditions compared to air conditions. Furthermore, in the presence of liquid nitrogen, the metal matrix composite did not exhibit any microstructural defects, such as micro-cracks. Energy dispersive spectroscopy analysis also demonstrated that SiC had better penetration into the base material under cryogenic conditions compared to dry conditions. Manuscript profile -
Open Access Article
7 - Machinability Improvement of 17-4PH Stainless Steel by Cryogenic Cooling
Salman Khani Mohammad Razfar Masoud Farahnakyan -
Open Access Article
8 - Evaluating the effect of deep cryogenic heat treatment on microstructure, wear and tension properties of the GOST9HF-steel at tempering temperature from 150 to 650˚C
kamran aminiIn recent years, cryogenic-treatment is considered in order to improve of wear and hardness resistance of tool steels. Cryo-treatment is performed on steel before and after of tempering and quenching treatment, respectively. In this research, the effect of deep cryogeni MoreIn recent years, cryogenic-treatment is considered in order to improve of wear and hardness resistance of tool steels. Cryo-treatment is performed on steel before and after of tempering and quenching treatment, respectively. In this research, the effect of deep cryogenic treatment is investigated on the GOS9HF-steel. In this regard, the quenched-tempered and quenched-Cryo-treated samples are prepared after tempering treatment for 2hrs. then, impact of Cryo-treatment on value of retained austenite, fine carbide precipitations are evaluated by XRD, SEM and the amount of hardness, strength and wear resistance are measured by micro-hardness, tensile and wear tests. The wear test is conducted by pin-on-disc method. The results indicated that the amount of hardness and properties of wear and tensile in the Cryo-treated sample were rather than the quenched-tempered samples at all of tempering temperatures (i.e. from 150 to 650˚C). Additionally, with increase of tempering temperature, the amount of hardness, wear behavior and tensile property are decreased in both of Cryo-treated and quenched-tempered samples. This can be attributed to the softening of microstructure and the growing of grain sizes. Moreover, it was obvious that improving of Cryo-treated samples are related to the removing of retained austenite, precipitation of fine carbides and more appropriate distribution of these carbides. It is cleared that the Cryo-treatment causes to decrease of value of retained austenite from 12% to below of 1% at quenched-tempered and Cryo-treated samples, respectively. Finally, Cryo-treatment causes to increase of volume fracture of carbides to 52%. Manuscript profile