Dehydrogenation method for steel material and steel product, and production method for steel material and steel product
Provided is a dehydrogenation method capable of efficiently reducing hydrogen content in steel for thick or complexly-shaped steel materials and steel products in general. In a dehydrogenation method for a steel material, in a series of steel material production process including: a process of supplying a steel raw material; a process of subjecting the steel raw material to hot working; a process of inspecting a steel material obtained from the steel raw material; and a process of shipping the steel material, at least one of the steel raw material and the steel material at any stage from the supply process to the shipment process is subjected to, at least once, a sound wave irradiation treatment so that a sound pressure level at a surface of the at least one of the steel raw material and the steel material will be 30 dB or more.
1 . A dehydrogenation method for a steel material, wherein in a series of steel material production process including: a supply process of supplying a steel raw material; a hot working process of subjecting the steel raw material to hot working; an inspection process of inspecting a steel material obtained from the steel raw material; and a shipment process of shipping the steel material, at least one of the steel raw material and the steel material at any stage from the supply process to the shipment process is subjected to, at least once, a treatment of irradiating with sound waves, without contacting the steel raw material or the steel material, from a sound wave irradiator located apart from a surface of the steel raw material or the steel material and toward the surface, the sound wave irradiator includes a controller, a sound wave oscillator, a vibration transducer, a booster, a horn and a sound level meter, so that a sound pressure level at the surface of the at least one of the steel raw material and the steel material will be 30 dB or more and thereby hydrogen content in the steel material will be reduced.
2 . The dehydrogenation method according to claim 1 , wherein the series of steel material production process further includes a cold working process of subjecting the steel material after the hot working process to cold working.
3 . The dehydrogenation method according to claim 1 , wherein the sound waves have a frequency from 10 Hz to 100000 Hz.
4 . The dehydrogenation method according to claim 1 , wherein a sound wave irradiation time in the treatment of irradiating with the sound waves is 1 second or more.
5 . The dehydrogenation method according to claim 2 , wherein the sound waves have a frequency from 10 Hz to 100000 Hz.
6 . The dehydrogenation method according to claim 2 , wherein a sound wave irradiation time in the treatment of irradiating with the sound waves is 1 second or more.
7 . The dehydrogenation method according to claim 3 , wherein a sound wave irradiation time in the treatment of irradiating with the sound waves is 1 second or more.
8 . The dehydrogenation method according to claim 5 , wherein a sound wave irradiation time in the treatment of irradiating with the sound waves is 1 second or more.
9 . A dehydrogenation method of claim 1 , wherein hydrogen content in the steel material will be reduced by 10% or more.
10 . A dehydrogenation method of claim 1 , wherein the steel material during the inspection process stage is subjected, at least once, to the treatment of irradiating with sound waves.
11 . A dehydrogenation method of claim 1 , wherein the sound pressure level at the surface of the at least one of the steel raw material and the steel material will be 60 dB or more.