High-toughness steel and method for manufacturing the same
AssigneeChina Steel Corporation
InventorsShih-Ming KUO, Herng-Shuoh JANG, Ying-Hao WANG, Wen-Fang CHIU
Life of this patent
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Abstract
A method for manufacturing high-toughness steel includes the following steps. A steel billet is provided. The steel billet is subjected to a heating step, a hot rolling step, a spheroidizing step and a quenching and tempering heat treatment step to obtain the high-toughness steel. The steel billet includes a specific proportion of composition. After the steel billet undergoes the heating step, the hot rolling step and the spheroidizing step, the obtained spheroidized steel has good processability and formability. The high-toughness steel has good hardness and impact toughness.
Claims17
A method for manufacturing high-toughness steel, comprising:
- providing a steel billet, wherein a total weight of the steel billet is as 100 weight percent, the steel billet comprises:
- 0.3 weight percent to 0.35 weight percent of carbon;
- 0.01 weight percent to 0.1 weight percent of silicon;
- 0.8 weight percent to 1.4 weight percent of manganese;
- 0.6 weight percent to 0.8 weight percent of chromium;
- 0.025 weight percent to 0.045 weight percent of niobium;
- 0.02 weight percent to 0.03 weight percent of titanium;
- 0.0015 weight percent to 0.0025 weight percent of boron;
- and
- a balance being iron and inevitable impurities, wherein the steel billet excludes nickel, copper, molybdenum, vanadium and aluminum;
- performing a heating step on the steel billet, so as to obtain a heated steel billet;
- performing a hot rolling step on the heated steel billet, so as to obtain a rolled steel;
- performing a spheroidizing step on the rolled steel, so as to obtain a spheroidized steel;
- and
- performing a quenching and tempering heat treatment step on the spheroidized steel, so as to obtain the high-toughness steel.
A method for manufacturing high-toughness steel, comprising:
- providing a steel billet, wherein a total weight of the steel billet is as 100 weight percent, the steel billet further comprises:
- 0.3 weight percent to 0.35 weight percent of carbon;
- 0.01 weight percent to 0.1 weight percent of silicon;
- 0.8 weight percent to 1.4 weight percent of manganese;
- 0.6 weight percent to 0.8 weight percent of chromium;
- 0.025 weight percent to 0.045 weight percent of niobium;
- 0.02 weight percent to 0.03 weight percent of titanium;
- 0.0015 weight percent to 0.0025 weight percent of boron;
- and
- a balance being iron and inevitable impurities, wherein the steel billet excludes nickel, copper, molybdenum, vanadium and aluminum;
- performing a hot rolling step, so as to obtain a rolled steel;
- performing a wire drawing step on the rolled steel, so as to obtain a drawn rolled steel;
- performing a spheroidizing step on the drawn rolled steel, so as to obtain a spheroidized steel;
- and
- performing a quenching and tempering heat treatment step on the spheroidized steel, so as to obtain the high-toughness steel, wherein the quenching and tempering heat treatment step comprises:
- an austenitization treatment, wherein an austenitization temperature of the austenitization treatment is 840° C. to 870° C., and an austenitization temperature holding time of the austenitization treatment is 1 hour to 2 hours;
- and a tempering treatment after the austenitization treatment, wherein a tempering temperature of the tempering treatment is 200° C. to 250° C., and a tempering temperature holding time of the tempering treatment is 1 hour to 2 hours.
Dependencies are inferred from the claim text.