Abstract: A process for crushing a hafnium (Hf) crystal bar comprises the steps of maintaining the Hf crystal bar at an extremely low temperature by holding the crystal bar in contact with a cryogenic refrigerant and crushing the crystal bar at the extremely low temperature by clamping and compressing the crystal bar between nickel (Ni)-base superalloy members. An apparatus for crushing the Hf crystal bar comprises a Ni-base superalloy-made container for containing the cryogenic refrigerant, the container having a bottom portion capable of being selectively opened and closed, a heat insulator for covering the container filled with the cryogenic refrigerant so as to maintain the interior of the container at the extremely low temperature, Ni-base superalloy-made pressing terminals for clamping the Hf crystal bar therebetween in the container, and a pressing device for exerting pressure on the pressing terminals so as to compress and crush the Hf crystal bar.

Abstract: A process for crushing a hafnium (Hf) crystal bar comprises the steps of maintaining the Hf crystal bar at an extremely low temperature by holding the crystal bar in contact with a cryogenic refrigerant and crushing the crystal bar at the extremely low temperature by clamping and compressing the crystal bar between nickel (Ni)-base superalloy members. An apparatus for crushing the Hf crystal bar comprises a Ni-base superalloy-made container for containing the cryogenic refrigerant, the container having a bottom portion capable of being selectively opened and closed, a heat insulator for covering the container filled with the cryogenic refrigerant so as to maintain the interior of the container at the extremely low temperature, Ni-base superalloy-made pressing terminals for clamping the Hf crystal bar therebetween in the container, and a pressing device for exerting pressure on the pressing terminals so as to compress and crush the Hf crystal bar.