Hot-pressed ultra-high creep resistant silicon carbide ceramics

發布時間: 2019-11-28

SEMINAR 

  Shanghai Institute of Ceramics, Chinese Academy of Sciences  

    中國科學院上海硅酸鹽研究所 

 

  Hot-pressed ultra-high creep resistant silicon carbide ceramics 

  SpeakerProf. RNDr. PAVOL ?AJGALíK 

  Slovak Academy of Sciences, Bratislava, Slovakia 

 

時間:1129日(周五)下午15:00 

地點:長寧園區四號樓十四樓第一會議室 

聯系人:江東亮院士,張景賢研究員(52412167 

 

  Freeze-granulated and afterwards under infrared lamp annealed silicon carbide powder was densified to the full density without any sintering aids by hot-pressing/ultra-rapid hot-pressing at 1850 °C. This densification temperature is at least 150-200 °C lower compared to the up to now known solid state sintered silicon carbide powders. Presented silicon carbide hot-pressed ceramics have excellent mechanical properties. Samples densified by ultra-rapid hot-pressing have also full density and hardness of 27.4 GPa. Partial phase transformation beta/alpha - SiC was observed in the granulated and hot-pressed/rapid hot-pressed samples.  

  Creep rate of rapid hot-pressed samples at 1450 °C and 100 MPa load in 4-point bending test is 3.8 x 10-9 s-1 and at 1400 °C and the same load conditions is 9.9 x 10-10 s-1.  

  Creep rate of the same at load of 400 MPa and temperature of 1750 °C at a comprersion mode was only 10-7 s-1. This is the lowest creep rate of SiC at such conditions found in the literature. Enhanced beta/alpha SiC phase transformation was observed after the creep test.  

  The oxidation behaviour of this way prepared SiC ceramics at 1350-1450°C/0-204h was investigated This way prepared SiC ceramics is characterised by an high oxidation resistance (4.91x10-5 mg2/cm4h at 1450°C).  

国产激情久久久久动态图,国产亚洲精品无码成人,国产麻豆精品一区二区三区,国产另类AV综合图区_主页