A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressurele...A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressureless sintering of a green bulk coated with a thin layer of low coefficient of thermal expansion(CTE).The stress level can be controlled by changing the cross-section area ratio,Young's modulus ratio and CTE ratio of the coating.Pre-stressed ZrO_(2) ceramics coated with Al_(2)O_(3) can achieve a flexural strength of 1330±52MPa,45% higher than their uncoated counterpart.Similarly,the flexural strength of building porcelain tiles is increased by 70%,from 67±3 MPa to 114±5MPa.The damage tolerance of pre-stressed ZrO_(2) ceramics is excellent with a high residual strength of ~1200 MPa in a thermal shock test at 325℃.This simple technique can improve the mechanical performance of ceramic components with no limitation of size and shape.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.51472227)General Technology Promotion Project of Industrial Technology in Basic Public Service Capacity Improvement and Industry Quality(Grant No.0714-EMTC-02-00573/6).
文摘A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressureless sintering of a green bulk coated with a thin layer of low coefficient of thermal expansion(CTE).The stress level can be controlled by changing the cross-section area ratio,Young's modulus ratio and CTE ratio of the coating.Pre-stressed ZrO_(2) ceramics coated with Al_(2)O_(3) can achieve a flexural strength of 1330±52MPa,45% higher than their uncoated counterpart.Similarly,the flexural strength of building porcelain tiles is increased by 70%,from 67±3 MPa to 114±5MPa.The damage tolerance of pre-stressed ZrO_(2) ceramics is excellent with a high residual strength of ~1200 MPa in a thermal shock test at 325℃.This simple technique can improve the mechanical performance of ceramic components with no limitation of size and shape.
