Hot isostatic pressing apparatus and hot isostatic pressing method

A hot isostatic pressing apparatus (HIP apparatus) comprises a vertically cylindrical high-pressure vessel comprising a high-pressure cylinder and upper and lower lids and a bottomed cylindrical casing capable of housing workpieces and a resistance-wire heater a heat insulating structure equipped with a gas flow regulating valve and formed in a bottomed cylindrical shape on the outside of the casing so as to cover the casing and a heat sink having a water cooling mechanism provided in the space defined by the heat insulating structure and the inner surface of the high-pressure cylinder which are provided within the high-pressure vessel; and a pressure medium gas stirring fan for promoting the temperature uniformity of the space of the treatment chamber for housing the workpieces the stirring fan being arranged on the lower lid side within the casing whereby the cooling to a temperature range of 100° C. or lower which allows a quenching treatment and the safe manual handling of workpieces can be efficiently performed.