JP2004169093A5

JP2004169093A5 -

Info

Publication number: JP2004169093A5
Application number: JP2002335270A
Authority: JP
Filing date: 2002-11-19
Publication date: 2005-03-10
Anticipated expiration: 2022-11-19

Description

【発明の名称】レーザ切断性が優れた厚鋼板及びその製造法Patent application title: Thick steel plate with excellent laser cutting ability and method for producing the same

【０００１】
【発明が属する技術分野】
本発明は建設機械、建築、橋梁分野等で使用されるレーザ切断性が優れた厚鋼板及びその製造法に関するものである。[0001]
[Technical field to which the invention belongs]
The present invention relates to a thick steel plate excellent in laser cutting ability used in construction machines, buildings, bridges and the like, and a method of manufacturing the same.

【００１１】
（１）質量％で、
Ｃ：０．０６〜０．３％、
Ｓｉ：０．５％以下、
Ｍｎ：０．４〜１．５％、
Ｐ：０．０１５％以下、
Ｓ：０．０１％以下、
Ａｌ：０．０５％以下、
Ｏ：０．００３５％以下、
Ｎ：０．００６％以下
を含有し、残部が鉄および不可避的不純物からなり、鋼板のスケール中の空孔（ボイド）率とスケールと地鉄界面の剥離割合の合計が１５％以上であることを特徴とするレーザ切断性が優れた厚鋼板。
（２）更に鋼成分が質量％で、
Ｔｉ：０．０２％以下、
Ｎｂ：０．０６％以下、
Ｖ：０．０４％以下、
Ｎｉ：０．３％以下、
Ｃｕ：０．３％以下、
Ｍｏ：０．７％以下
の内の１種または２種以上を更に加えたことを特徴とする上記（１）記載のレーザ切断性が優れた厚鋼板。
（３）質量％で、
Ｃ：０．０６〜０．３％、
Ｓｉ：０．５％以下、
Ｍｎ：０．４〜１．５％、
Ｐ：０．０１５％以下、
Ｓ：０．０１％以下、
Ａｌ：０．０５％以下、
Ｏ：０．００３５％以下、
Ｎ：０．００６％以下
を含有し、残部が鉄および不可避的不純物からなる鋼を連続鋳造法によってスラブとし、その後１１００℃以下の温度に再加熱後、圧延開始時にデスケーリングによりスケールを排除し、圧延をＴａ±２０℃の温度で終了し、その後放冷して鋼板のスケール中の空孔（ボイド）率とスケールと地鉄界面の剥離割合の合計が１５％以下とすることを特徴とするレーザ切断性が優れた厚鋼板の製造法。
ここで、Ｔａ＝１．２５Ｔｓ−４４０（℃）
Ｔａ：圧延終了温度（℃）Ｔｓ：スラブ加熱温度（℃）[0011]
(1) mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: 0.006% or less
Laser cuttability characterized in that the remainder is composed of iron and unavoidable impurities, and the sum of the void ratio in the scale of the steel plate and the peeling ratio of the scale and the ground iron interface is 15% or more Has excellent steel plate.
(2) Furthermore, the steel composition is in mass%,
Ti: 0.02% or less,
Nb: 0.06% or less,
V: 0.04% or less,
Ni: 0.3% or less,
Cu: 0.3% or less,
Mo: 0.7% or less of one or more types are further added, The steel sheet having excellent laser-cuttability according to the above (1), characterized in that
( 3 ) mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: A steel containing 0.006% or less, the balance being iron and unavoidable impurities, is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. and then scale is eliminated by descaling at the start of rolling , Finish rolling at a temperature of Ta ± 20 ° C, and then allow to stand to cool, and the total of the void ratio in the scale of the steel plate and the exfoliation ratio of the scale and the ground iron interface is 15% or less. Manufacturing method of thick steel plate with excellent laser cutting ability.
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

【００１２】
（４）質量％で、
Ｃ：０．０６〜０．３％、
Ｓｉ：０．５％以下、
Ｍｎ：０．４〜１．５％、
Ｐ：０．０１５％以下、
Ｓ：０．０１％以下、
Ａｌ：０．０５％以下、
Ｏ：０．００３５％以下、
Ｎ：０．００６％以下
を含有し、残部が鉄および不可避的不純物からなる鋼を連続鋳造法によってスラブとし、その後１１００℃以下の温度に再加熱後、圧延開始時にデスケーリングによりスケールを排除し、圧延をＴａ±２０℃の温度で終了し、その後水冷して鋼板のスケール中の空孔（ボイド）率とスケールと地鉄界面の剥離割合の合計が１５％以下とすることを特徴とするレーザ切断性が優れた厚鋼板の製造法。
ここで、Ｔａ＝１．２５Ｔｓ−４４０（℃）
Ｔａ：圧延終了温度（℃）Ｔｓ：スラブ加熱温度（℃）[0012]
( 4 ) mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: A steel containing 0.006% or less, the balance being iron and unavoidable impurities, is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. and then scale is eliminated by descaling at the start of rolling , Finish rolling at a temperature of Ta ± 20 ° C, and then water cooling to make the sum of the void ratio in the scale of the steel plate and the exfoliation ratio of the scale and the interface of the ground iron 15% or less A method of manufacturing thick steel plate with excellent laser cutting ability.
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

【００１３】
（５）質量％で、
Ｃ：０．０６〜０．３％、
Ｓｉ：０．５％以下、
Ｍｎ：０．４〜１．５％、
Ｐ：０．０１５％以下、
Ｓ：０．０１％以下、
Ａｌ：０．０５％以下、
Ｏ：０．００３５％以下、
Ｎ：０．００６％以下
を含有し、
Ｔｉ：０．０２％以下、
Ｎｂ：０．０６％以下、
Ｖ：０．０４％以下、
Ｎｉ：０．３％以下、
Ｃｕ：０．３％以下、
Ｍｏ：０．７％以下
の内の１種または２種以上を更に加え、残部が鉄および不可避的不純物からなる鋼を連続鋳造法によってスラブとし、その後１１００℃以下の温度に再加熱後、圧延開始時にデスケーリングによりスケールを排除し、圧延をＴａ±２０℃の温度で終了し、その後放冷して鋼板のスケール中の空孔（ボイド）率とスケールと地鉄界面の剥離割合の合計が１５％以下とすることを特徴とするレーザ切断性が優れた厚鋼板の製造法。
ここで、Ｔａ＝１．２５Ｔｓ−４４０（℃）
Ｔａ：圧延終了温度（℃）Ｔｓ：スラブ加熱温度（℃）[0013]
( 5 ) mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: 0.006% or less is contained,
Ti: 0.02% or less,
Nb: 0.06% or less,
V: 0.04% or less,
Ni: 0.3% or less,
Cu: 0.3% or less,
Mo: 0.7% or less of one or more is further added, and a steel containing the balance of iron and unavoidable impurities is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. or less, and then rolled. At the start, the scale is eliminated by descaling, the rolling is ended at a temperature of Ta ± 20 ° C., and then allowed to cool, and the sum of the void ratio in the scale of the steel plate and the peeling ratio of the scale and the ground iron interface is A method for producing a thick steel plate excellent in laser-cuttability, characterized in that it is 15% or less.
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

【００１４】
（６）質量％で、
Ｃ：０．０６〜０．３％、
Ｓｉ：０．５％以下、
Ｍｎ：０．４〜１．５％、
Ｐ：０．０１５％以下、
Ｓ：０．０１％以下、
Ａｌ：０．０５％以下、
Ｏ：０．００３５％以下、
Ｎ：０．００６％以下
を含有し、
Ｔｉ：０．０２％以下、
Ｎｂ：０．０６％以下、
Ｖ：０．０４％以下、
Ｎｉ：０．３％以下、
Ｃｕ：０．３％以下、
Ｍｏ：０．７％以下
の内の１種または２種以上を更に加え、残部が鉄および不可避的不純物からなる鋼を連続鋳造法によってスラブとし、その後１１００℃以下の温度に再加熱後、圧延開始時にデスケーリングによりスケールを排除し、圧延をＴａ±２０℃の温度で終了し、その後水冷して鋼板のスケール中の空孔（ボイド）率とスケールと地鉄界面の剥離割合の合計が１５％以下とすることを特徴とするレーザ切断性が優れた厚鋼板の製造法。
ここで、Ｔａ＝１．２５Ｔｓ−４４０（℃）
Ｔａ：圧延終了温度（℃）Ｔｓ：スラブ加熱温度（℃）[0014]
( 6 ) mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: 0.006% or less is contained,
Ti: 0.02% or less,
Nb: 0.06% or less,
V: 0.04% or less,
Ni: 0.3% or less,
Cu: 0.3% or less,
Mo: 0.7% or less of one or more is further added, and a steel containing the balance of iron and unavoidable impurities is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. or less, and then rolled. At the start, the scale is eliminated by descaling, the rolling is finished at a temperature of Ta ± 20 ° C., and then water cooling is performed, and the sum of the void ratio in the scale of the steel plate and the peeling ratio of the scale and the ground iron interface is 15 %. The method for producing a thick steel plate excellent in laser-cuttability, characterized in that
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

Claims

In mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: 0.006% or less
Laser cuttability characterized in that the remainder is composed of iron and unavoidable impurities, and the sum of the void ratio in the scale of the steel plate and the peeling ratio of the scale and the ground iron interface is 15% or more Has excellent steel plate.

Furthermore, the steel composition is in mass%,
Ti: 0.02% or less,
Nb: 0.06% or less,
V: 0.04% or less,
Ni: 0.3% or less,
Cu: 0.3% or less,
Mo: 0.7% or less
The steel plate excellent in laser-cuttability according to claim 1, characterized in that one or more of them are further added.

In mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: A steel containing 0.006% or less, the balance being iron and unavoidable impurities, is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. and then scale is eliminated by descaling at the start of rolling , Finish rolling at a temperature of Ta ± 20 ° C, and then allow to stand to cool, and the total of the void ratio in the scale of the steel plate and the exfoliation ratio of the scale and the ground iron interface is 15% or less. Manufacturing method of thick steel plate with excellent laser cutting ability.
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

In mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: A steel containing 0.006% or less, the balance being iron and unavoidable impurities, is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. and then scale is eliminated by descaling at the start of rolling , Finish rolling at a temperature of Ta ± 20 ° C, and then water cooling to make the sum of the void ratio in the scale of the steel plate and the exfoliation ratio of the scale and the interface of the ground iron 15% or less A method of manufacturing thick steel plate with excellent laser cutting ability.
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

In mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: 0.006% or less is contained,
Ti: 0.02% or less,
Nb: 0.06% or less,
V: 0.04% or less,
Ni: 0.3% or less,
Cu: 0.3% or less,
Mo: 0.7% or less of one or more is further added, and a steel containing the balance of iron and unavoidable impurities is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. or less, and then rolled. At the start, the scale is eliminated by descaling, the rolling is ended at a temperature of Ta ± 20 ° C., and then allowed to cool, and the sum of the void ratio in the scale of the steel plate and the peeling ratio of the scale and the ground iron interface is A method for producing a thick steel plate excellent in laser-cuttability, characterized in that it is 15% or less.
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)

In mass%,
C: 0.06 to 0.3%
Si: 0.5% or less,
Mn: 0.4 to 1.5%,
P: 0.015% or less,
S: 0.01% or less,
Al: 0.05% or less,
O: 0.0035% or less,
N: 0.006% or less is contained,
Ti: 0.02% or less,
Nb: 0.06% or less,
V: 0.04% or less,
Ni: 0.3% or less,
Cu: 0.3% or less,
Mo: 0.7% or less of one or more is further added, and a steel containing the balance of iron and unavoidable impurities is made into a slab by continuous casting, and thereafter reheated to a temperature of 1100 ° C. or less, and then rolled. At the start, the scale is eliminated by descaling, the rolling is finished at a temperature of Ta ± 20 ° C., and then water cooling is performed, and the sum of the void ratio in the scale of the steel plate and the peeling ratio of the scale and the ground iron interface is 15 %. The method for producing a thick steel plate excellent in laser-cuttability, characterized in that
Here, Ta = 1.25Ts-440 (° C.)
Ta: End of rolling temperature (° C) Ts: Slab heating temperature (° C)