No abstract

No abstract

No abstract

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αÜ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j°°ã˺mÈÓ© ÓÒ}ËãËm©Ë äȯÒÓ©Ë }ºä¹ºÏÒ© ȯäÒ¯ºmÈÓÓ©Ë Èã ÁÈ}ȯҺä }¯ËäÓÒ«¯ÈÏãÒÓ©² }ºÓËÓ¯ÈÒ® º äÈ° |¯ÈÏ© ÒϺÈmãÒmÈãÒ° ä˺ºä°ä ËÒmÈÓÒ« ¹º¯º}ºm°¹º°ãËÒä ¹¯ºË°°ºä ¹º¯º}ºmº® ˲ӺãºÒÒ ºãËÓÓ©Ë }ºä¹ºÏÒÒºÓÓ©Ë ¹º¯º}Ò 6L&1L ¹ºm˯ÈãÒ° ²ºãºÓºä ¹¯Ë°°ºmÈÓÒ ¹¯Ò lÈ m ºÓºº°Óº® ºãºm}Ë°¹º°ãËÒä°¹Ë}ÈÓÒËä ¹¯Ò Sv m È亰ÁË¯Ë mºº¯ºÈϺ º¯º}Ò 6L&1L Ò ÒÏäËã ËÓÓ©Ë º¹ºãÒ¯ºmÈÓÓ©Ë }ºÓ°ºãÒÒ¯ºmÈÓÓ©Ë }ºä¹ºÏÒ © Ò°°ã˺mÈÓ© ä˺ÈäÒ°}ÈÓүˮ ªãË}¯ºÓÓº® äÒ}¯º°}º¹ÒÒ Ò¯ËÓËÓº°¯}¯ Óºº ÈÓÈãÒÏÈ lÒ}¯º°¯}¯© }ºä¹ºÏÒºm 6L&1L ¹ºãËÓÓ©² ¹º°ãË°¹Ë}ÈÓÒ« ²È¯È} ,661 )XQFWLRQDO 0DWHULDOV 1R S GRLKWWSVGRLRUJIP Û 67& ,QVWLWXWH IRU 6LQJOH &U\VWDOV )XQFWLRQDO PDWHULDOV

Nickel/detonated nanodiamond composites were prepared using the powder metallurgy technique. Detonated nanosized diamond particles were reinforced in the nickel matrix. The investigated powder was used to prepare homogenous diamond/nickel composite mixtures with different detonated nanodiamond content of weight percentage (0.2, 0.4, 0.6, and 0.8 wt.%). The produced mixtures were cold pressed into a cylindrical die shape under compaction pressure of 400 MPa followed by sintering at 1,000°C for 120 min under a controlled atmosphere of 1:3 hydrogen/nitrogen gas mixture. Phase identification and microstructure of the produced sintered samples were investigated using X-ray diffraction and scanning electron microscope, respectively. The results of the microstructure show a good distribution of the detonated nanodiamond in the nickel matrix, especially in the 0.8 wt% diamond/nickel sintered sample. The densities of the obtained sintered samples were measured by applying the Archimedes principal. As the detonated nanodiamond content was increased in the nickel matrix, the density of the sintered samples was decreased. The thermal expansion, electrical conductivity, and hardness of the produced diamond/nickel composites were measured. The coefficient of thermal expansion and electrical conductivity were decreased, but the hardness was increased by increasing the detonated nanodiamond weight percentage.

Two different concepts of electrically assisted (EA) rapid heating of Al-Si coated hot-stamping steels are compared. In "along the surface" EA heating (or simply EA surface heating), the electric current is simply applied to a specimen by clamping the each end of the specimen length with a set of flat rectangular electrodes. In "through the thickness" EA heating (or simply EA thickness heating), the electric current is applied to a specimen by attaching a set of electrodes with multiple contact points on upper and lower surfaces of the specimen. While the EA surface heating generally requires a shorter heating time due to a higher electrical resistance in the length direction, the EA thickness heating also may provide a technical advantage that the heating area can be more easily configured in a case of partial austenization.