Effect of Pressure on Thermal Stability and Decomposition of KDP Crystal

Effect of pressure on thermal behavior of KDP crystals is investigated by using the in-situ infrared reflective spectra.Compared with that under normal atmosphere,the onset temperature of decomposition under pressure of 1 MPa is improved to from 210℃to 213℃,suggesting that the thermal stability of KDP is enhanced.Under pressure of 2 MPa,the thermal stability is deteriorated and KDP begins to decompose at 183℃.Under normal atmosphere KDP decomposes in route of translating to K_(4)P_(2)O_(7)firstly,and then to KPO_(3).Under pressures of 1 MPa and 2MPa,KDP translates to KPO_(3)directly without any other polymeric intermediates.