CN105839434B - 一种瞬时淬火改性制备预应力钢绞线的方法 - Google Patents

一种瞬时淬火改性制备预应力钢绞线的方法 Download PDF

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CN105839434B
CN105839434B CN201610267278.4A CN201610267278A CN105839434B CN 105839434 B CN105839434 B CN 105839434B CN 201610267278 A CN201610267278 A CN 201610267278A CN 105839434 B CN105839434 B CN 105839434B
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袁春华
盛海丰
高玉刚
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Xinfeng Tianjin prestressed steel strand Co., Ltd.
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Abstract

本发明公开了一种瞬时淬火改性制备预应力钢绞线的方法,属于预应力钢绞线制备技术领域。本发明取Fe、C、Si等物质混合冶炼成钢,精轧成盘条钢丝,经洗涤、干燥后绞合成钢绳,再经预热、二次保温煅烧、二次铅浴冷却,再于冰水混合物中冷却,乙酸乙酯洗涤、干燥制得预应力钢绞线。本发明的有益效果是:本发明制备步骤简单,所得产品碳元素的原子活性高于其他产品23.2%以上,不易位错;材料性能稳定性好,钢绳中氢含量低于1.23ppm,不易产生裂纹。

Description

一种瞬时淬火改性制备预应力钢绞线的方法
技术领域
本发明涉及一种瞬时淬火改性制备预应力钢绞线的方法,属于预应力钢绞线制备技术领域。
背景技术
预应力钢绞线是高强度钢丝构成的绞合钢缆,并经消除应力处理(稳定化处理),适合预应力混凝土或类似用途。采用高碳钢盘条,经过表面处理后冷拔成钢丝,然后按钢绞线结构将一定数量的钢丝绞合成股,再经过消除应力的稳定化处理过程而成。为延长耐久性,钢丝上可以有金属或非金属的镀层或涂层,如镀锌、涂环氧树脂等。为增加与混凝土的握裹力,表面可以有刻痕等。模拔的预应力钢绞线在绞合后经过一次模具压缩过程,结构更加密实,表层更加适合锚具抓握。制作无粘结预应力钢绞线采用普通的预应力钢绞线,涂防腐油脂或石蜡后包高密度聚乙烯(HDPE)就成。现有技术中,钢材原料成分中碳元素的原子活性较低,各原子形成的气团不能与位错形成强烈的相互作用,外界无需提供较大的应力就能开动位错,从而使性能很不稳定,同时钢棒锻坯中氢含量在2.0ppm以上,钢棒锻坯容易产生裂纹从而诱发氢致裂纹及氢致延迟滞后裂纹。
发明内容
本发明所要解决的技术问题:针对预应力钢绞线钢材原料成分中碳元素的原子活性较低,各原子形成的气团不能与位错形成强烈的相互作用,外界无需提供较大的应力就能开动位错,性能稳定较差的弊端,提供了一种取Fe、C、Si等物质混合冶炼成钢,精轧成盘条钢丝,经洗涤、干燥后绞合成钢绳,再经预热、二次保温煅烧、二次铅浴冷却,再于冰水混合物中冷却,乙酸乙酯洗涤、干燥制得预应力钢绞线的方法。本发明制备步骤简单,所得产品碳元素的原子活性高,性能稳定性好,不易产生裂纹。
为解决上述技术问题,本发明采用如下所述的技术方案是:
(1)按重量份数计,分别称量86~93份Fe、1~2份C、2~3份Si、1~3份Mn、0.5~1.0份P、0.5~1.0份S、0.9~1.5份Cr、0.1~0.5份Ni、0.9~1.5份Cu和0.1~0.5份V置于冶炼炉中,在1950~2000℃下冶炼成钢,并精轧至直径为5mm盘条钢丝;
(2)取6股上述制备的盘条钢丝用无水乙醇洗涤3~5次,待自然晾干后,再将6股洗涤后的盘条钢丝置于绞线机中,绞合成钢绳,控制绞合力大小为55~60MPa;
(3)待绞合完成后,将钢绳置于电阻炉中,在650~700℃下预热1~2h,随后按8℃/min速率程序升温至950~1000℃,保温煅烧1~2h,再按10℃/min速率程序升温至1200~1300℃,继续保温煅烧2~3h;
(4)待保温煅烧完成后,将其置于1000℃铅浴中,铅浴冷却1~2h,待钢绳降温至1000℃后,将其迅速置于550~600℃铅浴中,继续静置铅浴25~30min,随后将钢绳迅速取出,再将其淬入冰水混合物中,冷却2~3h;
(5)待钢绳温度冷却至室温后,将其取出并自然晾干,随后用乙酸乙酯洗涤3~5次,再在65~80℃烘箱中干燥6~8h,即可制备得一种预应力钢绞线。
本发明制得的预应力钢绞线破断载荷267~275kN,1%伸长载荷246~253kN,延伸率为5.0~6.1%,弹性模量为1.99~2.07×105MPa,1000h松弛率为0.86~1.26%,抗拉强度为1880~1960MPa,断面收缩率>25.6%。
本发明与其他方法相比,有益技术效果是:
(1)本发明制备步骤简单,所得产品碳元素的原子活性高于其他产品23.2%以上,不易位错;
(2)材料性能稳定性好,钢绳中氢含量低于1.23ppm,不易产生裂纹。
具体实施方式
首先按重量份数计,分别称量86~93份Fe、1~2份C、2~3份Si、1~3份Mn、0.5~1.0份P、0.5~1.0份S、0.9~1.5份Cr、0.1~0.5份Ni、0.9~1.5份Cu和0.1~0.5份V置于冶炼炉中,在1950~2000℃下冶炼成钢,并精轧至直径为5mm盘条钢丝;然后取6股上述制备的盘条钢丝用无水乙醇洗涤3~5次,待自然晾干后,再将6股洗涤后的盘条钢丝置于绞线机中,绞合成钢绳,控制绞合力大小为55~60MPa;待绞合完成后,将钢绳置于电阻炉中,在650~700℃下预热1~2h,随后按8℃/min速率程序升温至950~1000℃,保温煅烧1~2h,再按10℃/min速率程序升温至1200~1300℃,继续保温煅烧2~3h;再待保温煅烧完成后,将其置于1000℃铅浴中,铅浴冷却1~2h,待钢绳降温至1000℃后,将其迅速置于550~600℃铅浴中,继续静置铅浴25~30min,随后将钢绳迅速取出,再将其淬入冰水混合物中,冷却2~3h;最后待钢绳温度冷却至室温后,将其取出并自然晾干,随后用乙酸乙酯洗涤3~5次,再在65~80℃烘箱中干燥6~8h,即可制备得一种预应力钢绞线。
实例1
首先按重量份数计,分别称量86份Fe、2份C、3份Si、3份Mn、1.0份P、1.0份S、1.5份Cr、0.5份Ni、1.5份Cu和0.5份V置于冶炼炉中,在1950℃下冶炼成钢,并精轧至直径为5mm盘条钢丝;然后取6股上述制备的盘条钢丝用无水乙醇洗涤3次,待自然晾干后,再将6股洗涤后的盘条钢丝置于绞线机中,绞合成钢绳,控制绞合力大小为55MPa;待绞合完成后,将钢绳置于电阻炉中,在650℃下预热1h,随后按8℃/min速率程序升温至950℃,保温煅烧1h,再按10℃/min速率程序升温至1200℃,继续保温煅烧2h;再待保温煅烧完成后,将其置于1000℃铅浴中,铅浴冷却1h,待钢绳降温至1000℃后,将其迅速置于550℃铅浴中,继续静置铅浴25min,随后将钢绳迅速取出,再将其淬入冰水混合物中,冷却2h;待钢绳温度冷却至室温后,将其取出并自然晾干,随后用乙酸乙酯洗涤3次,再在65℃烘箱中干燥6h,即可制备得一种预应力钢绞线。本发明制备步骤简单,所得产品碳元素的原子活性高于其他产品23.5%,不易位错;材料性能稳定性好,钢绳中氢含量为1.21ppm,不易产生裂纹;制得的预应力钢绞线破断载荷267kN,1%伸长载荷246kN,延伸率为5.0%,弹性模量为1.99×105MPa,1000h松弛率为0.86%,抗拉强度为1880MPa,断面收缩率为25.9%。
实例2
首先按重量份数计,分别称量90份Fe、1.5份C、2份Si、2份Mn、0.8份P、0.7份S、1.2份Cr、0.3份Ni、1.2份Cu和0.3份V置于冶炼炉中,在1975℃下冶炼成钢,并精轧至直径为5mm盘条钢丝;然后取6股上述制备的盘条钢丝用无水乙醇洗涤4次,待自然晾干后,再将6股洗涤后的盘条钢丝置于绞线机中,绞合成钢绳,控制绞合力大小为58MPa;待绞合完成后,将钢绳置于电阻炉中,在675℃下预热2h,随后按8℃/min速率程序升温至975℃,保温煅烧2h,再按10℃/min速率程序升温至1250℃,继续保温煅烧3h;再待保温煅烧完成后,将其置于1000℃铅浴中,铅浴冷却2h,待钢绳降温至1000℃后,将其迅速置于575℃铅浴中,继续静置铅浴28min,随后将钢绳迅速取出,再将其淬入冰水混合物中,冷却3h;待钢绳温度冷却至室温后,将其取出并自然晾干,随后用乙酸乙酯洗涤4次,再在72℃烘箱中干燥7h,即可制备得一种预应力钢绞线。本发明制备步骤简单,所得产品碳元素的原子活性高于其他产品23.9%,不易位错;材料性能稳定性好,钢绳中氢含量为1.15ppm,不易产生裂纹;制得的预应力钢绞线破断载荷271kN,1%伸长载荷249kN,延伸率为5.6%,弹性模量为2.04×105MPa,1000h松弛率为1.06%,抗拉强度为1920MPa,断面收缩率为26.3%。
实例3
首先按重量份数计,分别称量93份Fe、1份C、2份Si、1份Mn、0.5份P、0.5份S、0.9份Cr、0.1份Ni、0.9份Cu和0.1份V置于冶炼炉中,在2000℃下冶炼成钢,并精轧至直径为5mm盘条钢丝;然后取6股上述制备的盘条钢丝用无水乙醇洗涤5次,待自然晾干后,再将6股洗涤后的盘条钢丝置于绞线机中,绞合成钢绳,控制绞合力大小为60MPa;待绞合完成后,将钢绳置于电阻炉中,在700℃下预热2h,随后按8℃/min速率程序升温至1000℃,保温煅烧2h,再按10℃/min速率程序升温至1300℃,继续保温煅烧3h;待保温煅烧完成后,将其置于1000℃铅浴中,铅浴冷却2h,待钢绳降温至1000℃后,将其迅速置于600℃铅浴中,继续静置铅浴30min,随后将钢绳迅速取出,再将其淬入冰水混合物中,冷却3h;待钢绳温度冷却至室温后,将其取出并自然晾干,随后用乙酸乙酯洗涤5次,再在80℃烘箱中干燥8h,即可制备得一种预应力钢绞线。本发明制备步骤简单,所得产品碳元素的原子活性高于其他产品24.7%,不易位错;材料性能稳定性好,钢绳中氢含量1.09ppm,不易产生裂纹;制得的预应力钢绞线破断载荷275kN,1%伸长载荷253kN,延伸率为6.1%,弹性模量为2.07×105MPa,1000h松弛率为1.26%,抗拉强度为1960MPa,断面收缩率为26.9%。

Claims (1)

1.一种瞬时淬火改性制备预应力钢绞线的方法,其特征在于具体制备步骤为:
(1)按重量份数计,分别称量86~93份Fe、1~2份C、2~3份Si、1~3份Mn、0.5~1.0份P、0.5~1.0份S、0.9~1.5份Cr、0.1~0.5份Ni、0.9~1.5份Cu和0.1~0.5份V置于冶炼炉中,在1950~2000℃下冶炼成钢,并精轧至直径为5mm盘条钢丝;
(2)取6股上述制备的盘条钢丝用无水乙醇洗涤3~5次,待自然晾干后,再将6股洗涤后的盘条钢丝置于绞线机中,绞合成钢绳,控制绞合力大小为55~60MPa;
(3)待绞合完成后,将钢绳置于电阻炉中,在650~700℃下预热1~2h,随后按8℃/min速率程序升温至950~1000℃,保温煅烧1~2h,再按10℃/min速率程序升温至1200~1300℃,继续保温煅烧2~3h;
(4)待保温煅烧完成后,将其置于1000℃铅浴中,铅浴冷却1~2h,待钢绳降温至1000℃后,将其迅速置于550~600℃铅浴中,继续静置铅浴25~30min,随后将钢绳迅速取出,再将其淬入冰水混合物中,冷却2~3h;
(5)待钢绳温度冷却至室温后,将其取出并自然晾干,随后用乙酸乙酯洗涤3~5次,再在65~80℃烘箱中干燥6~8h,即可制备得一种预应力钢绞线。
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