CN109518075A - 一种高强度耐磨实心铁球及其生产工艺 - Google Patents

一种高强度耐磨实心铁球及其生产工艺 Download PDF

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CN109518075A
CN109518075A CN201811297952.9A CN201811297952A CN109518075A CN 109518075 A CN109518075 A CN 109518075A CN 201811297952 A CN201811297952 A CN 201811297952A CN 109518075 A CN109518075 A CN 109518075A
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马腾
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    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
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    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
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    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
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    • C23C8/52Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using liquids, e.g. salt baths, liquid suspensions more than one element being applied in one step
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    • C23C8/56Carbo-nitriding of ferrous surfaces
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    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
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Abstract

本发明公开了一种高强度耐磨实心铁球及其生产工艺,涉及机械加工技术领域。本发明铁球由以下重量百分数的成分组成:C0.31%~0.42%、N<0.05%,Si0.17%~0.37%、Mn0.5%~0.8%、P<0.035%、S<0.035%、Cr<0.25%、Cu<0.25%、Ni<0.3%,其余为Fe,铁球的表面硬度为95‑110HRC,冲击韧性为65‑85J/cm2。本发明通过利用低碳25号钢无回火脆性倾向的特性,在工艺上免去回火工序,通过炭氮共渗和分级淬火,得到更高硬度、耐磨性的铁球外层,并且铁球心部组织强度也可受到增强,从而获得高冲击韧性,提高铁球强度,且工艺简单,利于提高自动化轧制的效率。

Description

一种高强度耐磨实心铁球及其生产工艺
技术领域
本发明属于机械加工技术领域,特别是涉及一种高强度耐磨实心铁球,及一种高强度耐磨实心铁球的生产工艺。
背景技术
目前,钢球生产方式一般有锻造、轧制、半固态成型及铸造四大类;由于行业习惯及受限于选矿工业等一-些特殊场合的使用条件、综合环境和背景,常规的钢球生产方式以锻造与轧制球占有相当大的比例。这其中,热轧钢球作为一种全新的轧制工艺技术,是球磨钢球制造业的工艺技术突破,正在逐渐替代锻造钢球,与锻造等方式相比,热轧钢球工艺具有以下特点:热轧方式生产效率高、产量大、轧球生产机械化、自动化程度极高,用人少,人为因素干扰小、质量稳定;硬度高、淬透性好、金相组织致密、晶粒细小、不变形,钢球由始至终不会变形、不失圆,耐磨性能好,冲击韧性高达12-35J/cm2,破碎率小于1%;能耗低、无污染、劳动强度低、生产成本较低;成形好,几何公差小,质量稳定;磨损率低,使用寿命长,是现有铸造铁球、锻造钢球的2-5倍,且价格相当;钢球整体硬度高,其表面硬度可达到55-65HRC,体积硬度达到50-62HRC,内外硬度均衡,硬度差<5HRC,且硬度梯度分布均匀;冲击韧性高达12-35J/cm2;破碎率低,抗剥碎及抗破碎性能是一般铸锻钢球的10倍以上,落球冲击次数2万次以上,实际破碎率不超过1%,接近于无破碎;基于上述优点,热轧钢球产品在各类黑色和有色金属矿山选矿厂、火力发电厂、水泥厂、耐火材料厂等行业得到广泛应用,受到国内外客户的一致好评。目前的热轧钢球生产一般采用塑性较好的中碳钢,再利用淬火和回火热处理工艺提高钢球强度,然而,钢球在淬火后受回火脆性影响,若回火处理不当,会导致钢球抗冲击性变差,工艺难度相对较大,并且这种工艺方法不适于大直径钢球的加工,会导致钢球淬硬层深度小,内外层硬度差较大,整体强度降低,钢球形变量大,而尺寸不精准。
发明内容
本发明的目的在于提供一种高强度耐磨实心铁球及其生产工艺,工艺简单,工序设计合理,生产的铁球具备高硬度、抗冲击强度和耐磨性。
本发明是通过以下技术方案实现的:
本发明为一种高强度耐磨实心铁球及其生产工艺,所述铁球由以下重量百分数的成分组成:C0.31%~0.42%、N<0.05%,Si0.17%~0.37%、Mn0.5%~0.8%、P<0.035%、S<0.035%、Cr<0.25%、Cu<0.25%、Ni<0.3%,其余为Fe,所述铁球的表面硬度为95-110HRC,冲击韧性为65-85J/cm2
进一步地,所述的一种高强度耐磨实心铁球的生产工艺,主要包括以下步骤:
SS01、将热轧圆钢棒原料置于燃气加热炉中加热至1180℃-1220℃,出炉温度为1050℃-1150℃;
SS02、出炉后钢棒进入斜轧钢球轧机中连续轧制成球形;
SS03、成形后的铁球经过在输送过程中空冷至840℃-860℃,再进入盐浴炉进行炭氮共渗,共渗温度为820℃-860℃;
SS04、经过炭氮共渗后的铁球直接在110℃-200℃热油或碱浴中分级淬火1-15min后取出空冷,得到成品实心铁球。
进一步地,所述热轧圆钢棒原料的材质为25号钢,且单根长度为3-4m。
进一步地,所述实心铁球炭氮共渗层与内层硬度差<3HRC。
进一步地,所述SS03中铁球输送过程还包括铁球筛选,所述铁球筛选的方法为,在钢球出料口设置射线探伤仪自动检测,通过闸门控制合格品进入与所述盐浴炉连接的导向通道,不合格品进入次品回收导向通道。
本发明具有以下有益效果:
本发明通过利用低碳25号钢无回火脆性倾向的特性,在工艺上免去回火工序,通过炭氮共渗和分级淬火,得到更高硬度、耐磨性的铁球外层,并且铁球心部组织强度也可受到增强,从而获得高冲击韧性,提高铁球强度,且工艺简单,利于提高自动化轧制的效率。
当然,实施本发明的任一产品并不一定需要同时达到以上所述的所有优点。
具体实施方式
下面将对本发明实施例中的技术方案进行清楚、完整地描述,显然,所描述的实施例仅仅是本发明一部分实施例,而不是全部的实施例。基于本发明中的实施例,本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其它实施例,都属于本发明保护的范围。
实施例一
SS01、将材质为25号钢的热轧圆钢棒原料置于燃气加热炉中加热至1180,出炉温度为1050℃;
SS02、出炉后钢棒进入斜轧钢球轧机中连续轧制成球形;
SS03、成形后的铁球经过在输送过程中空冷至840℃,再进入盐浴炉进行炭氮共渗,共渗温度为820℃;
SS04、经过炭氮共渗后的铁球直接在110℃热油或碱浴中分级淬火5min后取出空冷,得到成品实心铁球,金相组成为:C0.33%、N<0.01%,Si0.25%、Mn0.6%、P0.025%、S0.025%、Cr0.22%、Cu0.23%、Ni0.28%,其余为Fe,表面硬度为98HRC,冲击韧性为66J/cm2,炭氮共渗层与内层硬度差为2.7HRC。
实施例二
SS01、将材质为25号钢的热轧圆钢棒原料置于燃气加热炉中加热至1200℃,出炉温度为1100℃;
SS02、出炉后钢棒进入斜轧钢球轧机中连续轧制成球形;
SS03、成形后的铁球经过在输送过程中空冷至860℃,再进入盐浴炉进行炭氮共渗,共渗温度为860℃;
SS04、经过炭氮共渗后的铁球直接在200℃热油或碱浴中分级淬火15min后取出空冷,得到成品实心铁球,金相组成为:C0.40%、N0.04%,Si0.33%、Mn0.6%、P0.32%、S0.32%、Cr0.15%、Cu0.18%、Ni0.27%,其余为Fe,表面硬度为108HRC,冲击韧性为85J/cm2,炭氮共渗层与内层硬度差为1.3HRC。
实施例三
SS01、将材质为25号钢的热轧圆钢棒原料置于燃气加热炉中加热至1220℃,出炉温度为1150℃;
SS02、出炉后钢棒进入斜轧钢球轧机中连续轧制成球形;
SS03、成形后的铁球经过在输送过程中空冷至850℃,再进入盐浴炉进行炭氮共渗,共渗温度为840℃;
SS04、经过炭氮共渗后的铁球直接在160℃热油或碱浴中分级淬火10min后取出空冷,得到成品实心铁球,金相组成为:C0.36%、N<0.03%,Si0.25%、Mn0.72%、P0.031%、S0.027%、Cr0.18%、Cu0.21%、Ni0.28%,其余为Fe,表面硬度为102HRC,冲击韧性为73J/cm2,炭氮共渗层与内层硬度差为2HRC。
在本说明书的描述中,参考术语“一个实施例”、“示例”、“具体示例”等的描述意指结合该实施例或示例描述的具体特征、结构、材料或者特点包含于本发明的至少一个实施例或示例中。在本说明书中,对上述术语的示意性表述不一定指的是相同的实施例或示例。而且,描述的具体特征、结构、材料或者特点可以在任何的一个或多个实施例或示例中以合适的方式结合。
以上公开的本发明优选实施例只是用于帮助阐述本发明。优选实施例并没有详尽叙述所有的细节,也不限制该发明仅为所述的具体实施方式。显然,根据本说明书的内容,可作很多的修改和变化。本说明书选取并具体描述这些实施例,是为了更好地解释本发明的原理和实际应用,从而使所属技术领域技术人员能很好地理解和利用本发明。本发明仅受权利要求书及其全部范围和等效物的限制。

Claims (5)

1.一种高强度耐磨实心铁球,其特征在于:所述铁球由以下重量百分数的成分组成:C0.31%~0.42%、N<0.05%,Si0.17%~0.37%、Mn0.5%~0.8%、P<0.035%、S<0.035%、Cr<0.25%、Cu<0.25%、Ni<0.3%,其余为Fe,所述铁球的表面硬度为95-110HRC,冲击韧性为65-85J/cm2
2.根据权利要求1所述的一种高强度耐磨实心铁球的生产工艺,其特征在于,主要包括以下步骤:
SS01、将热轧圆钢棒原料置于燃气加热炉中加热至1180℃-1220℃,出炉温度为1050℃-1150℃;
SS02、出炉后钢棒进入斜轧钢球轧机中连续轧制成球形;
SS03、成形后的铁球经过在输送过程中空冷至840℃-860℃,再进入盐浴炉进行炭氮共渗,共渗温度为820℃-860℃;
SS04、经过炭氮共渗后的铁球直接在110℃-200℃热油或碱浴中分级淬火1-15min后取出空冷,得到成品实心铁球。
3.根据权利要求2所述的一种高强度耐磨实心铁球及其生产工艺,其特征在于,所述热轧圆钢棒原料的材质为25号钢,且单根长度为3-4m。
4.根据权利要求2所述的一种高强度耐磨实心铁球及其生产工艺,其特征在于,所述实心铁球炭氮共渗层与内层硬度差<3HRC。
5.根据权利要求2所述的一种高强度耐磨实心铁球及其生产工艺,其特征在于,所述SS03中铁球输送过程还包括铁球筛选,所述铁球筛选的方法为,在钢球出料口设置射线探伤仪自动检测,通过闸门控制合格品进入与所述盐浴炉连接的导向通道,不合格品进入次品回收导向通道。
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