真空感应炉熔炼合金钢时用氮化物增氮的试验研究

分析了真空度、温度和氮化物成分对钢中氮溶解度影响,并在50 k真空感应炉对不同化学成分的合金钢(/%:0.06～0.36C、≤3.23Si、≤2.20Al、≤9.00Cr)进行3种氮化物-氮化硅、氮化锰和氮化铬的增氮试验。结果表明,气相中氮气分压对钢液中氮溶解度影响最大;钢中Ti、Cr提高氮溶解度和氮化物的收得率;增加C含量则降低氮溶解度和氮化物的收得率;钢中含有一定量的铝,可以显著提高氮化物的收得率。40 kPa氩气压力,1 600～1 650℃时在硅钢、结构钢和9%Cr钢中氮化硅、氮化锰、氮化铬的收得率分别为25%～30%、30%～50%、60%～100%。     

真空感应炉冶炼含氮不锈钢的合金增氮工艺

试验研究了200 kg真空感应炉冶炼含氮不锈钢Cr13(0.04%～0.06%N)、Cr23Ni19(0.22%～0.28% N)和Cr22Ni9(0.15%～0.19%N)时,在(0.1～0.6)×10⁵Pa氩气或氮气下加氮化铬(56.2%Cr、7.33%N)增氮工艺。结果表明,在氮气保护下加氮化合金,氮回收率为80%以上;在氩气保护下加氮化合金,氮回收率仅为10%。提高炉内氮气压力,控制合适的加入温度,加入小粒度氮化铬,氮的回收率可达100%。     

用氮化铬、氮化锰冶炼高氮钢

 为了研究钢液增氮的新工艺,以钢液增氮的冶金热力学和动力学为基础,在10 kg感应炉上添加氮化铁合金以过饱和氮的方式来提高钢液最终氮含量,并对Cr18Mn18N和Cr23Mn17N两种实验材料的理论氮含量饱和值进行了计算。实验表明,采用氮化铬和氮化锰冶炼,钢液最终氮含量大幅度超过钢液与气相平衡时的氮含量,且氮化铬的增氮效果明显优于氮化锰。采用氮化铬冶炼,氮的收得率和氮的质量分数最高可达89%和098%。     

LF／VD法吹氮气冶炼含氮钢

1　前言随着生产经营的发展 ,品种钢的比例日益增大 ,其中要求有一定氮含量的低合金高强度钢的合同量也越来越多。而以前每年生产此类钢只有3～ 5炉 ,所采用的增 [N]工艺是在真空处理前后向钢液加入 40 0～ 50 0 kg的氮化锰合金 ,但利用氮化锰增 [N]有以下缺点 :1 )氮化锰的收得率低 ,且价格昂贵 ,增加成本 ;2 )氮化锰的收得率不稳定 ,生产中不好控制 ,影响正常生产 ;3)真空处理后向钢中加入氮化锰 ,在一定程度上会污染钢液 ,影响钢液的纯净度 ,恶化钢液质量。对此 ,我们针对此冶炼工艺作了吹氮增 [N]实验 ,首先在冶炼A633E钢时实验 L F/…     

氮化铬和氮化锰中夹杂物的对比实验

通过添加氮化铬和氮化锰冶炼高氮钢,对氮化铬和氮化锰中的夹杂物进行了对比实验.实验结果表明,在增氮效果上,氮化锰明显不如氮化铬,说明氮化锰的夹杂含量多于氮化铬.而通过对钢锭相同部位夹杂物的分析,钢锭最终夹杂物含量也多于氮化铬,表明氮化铬比氮化锰更纯净.     

50 t EAF EBT-60 t LF工艺冶炼GCr15钢的氮含量控制

研究了西宁特钢50 t EAF EBT-60 t LF冶炼GCr15高碳铬轴承钢时电弧炉泡沫渣操作、钢包炉(LF)吹氩精炼和成分微调、浇铸等工艺因素对钢中氮含量的影响.研究结果表明,电弧炉良好的泡沫渣操作,钢水脱碳量ΔC大于0.6%可使钢中氮含量降到(10～20)×10-6.在LF精炼时50 t钢水加200 kg碳粉可使钢水氮含量增加19×10-6,加合金可使钢水中平均氮含量增加4.2×10-6,浇铸过程钢水氮含量增加12×10-6.因此在LF精炼时减小碳和合金加入量可减少钢中氮含量的增加.     

1Mn15Cr17Ni2N高氮奥氏体不锈钢的研制

采用25 t EAF-VOD+LF-680 kg铸锭工艺冶炼0. 14%C-0.35%N 的奥氏体不锈钢1Mn15Cr17Ni2N。VOD精炼后,[N]为0.040%,[0]为0.0158%;通过LF吹氮45 min,吹氮量50 m³,分析得出[N]为0.139%, [O]为0.0033%,吹入氮气平均回收率为33.07%。再加人500 kg氮化铬(8.60%N)和150 kg氮化锰(5.13%N),取样分析[N]为0.35%, [O]为0.0029%,加氮化铬和氮化锰的氮综合回收率为87.41%。     

非调质曲轴钢的生产工艺研究与实践

为了使非调质曲轴钢中氮含量达到标准要求,本溪钢铁(集团)有限责任公司采用“转炉→LF→RH→矩形坯连铸”工艺,RH全程用氮气做提升气体,同时补加氮化锰合金,满足钢中氮含量要求.实践表明,此工艺可行,w(N)可稳定控制在(110～160)×10-6.另外,中包钢水中w(H)可以有效控制在2.5×10-6以下,钢材各项检验结果可以满足标准要求.     

超低碳奥氏体不锈钢00Cr18Ni10还原脱磷研究

在 2 5kg真空感应炉上用镁钙合金对超低碳奥氏体不锈钢 0 0Cr18Ni10进行了还原脱磷试验。通过充入工业纯氩使炉内压力为 6 6 .6 6kPa和精炼时的反应温度 14 5 0～ 15 0 0℃ ,加入镁钙合金 5 0kg t和助熔剂CaF2 11kg t,可使精炼后 0 0Cr18Ni10的磷含量进一步降低到 (5 0～ 6 0 )× 10 - 6 ,钢中氧、硫含量分别稳定降到(4～ 6 )× 10 - 6 和 15× 10 - 6 。     

80 t单嘴真空精炼炉冶金功能的生产实验分析

对80t单嘴真空精炼炉的冶金功能进行了生产实验分析,结果表明,单嘴精炼炉具有脱氢、脱氮、脱碳、脱氧、脱硫、化学升温、去除钢中夹杂物和合金成分调整等冶金功能。利用80t单嘴精炼炉精炼钢水,实验合结钢中氢含量可达(0.9～1.2) ×10^-6、氧含量(9～12) ×10^-6,超低碳钢中碳含量为(10～20) ×10^-6、氮含量(29～37) ×10^-6、钢水中硫含量为(10～30) ×10^-6;单嘴精炼炉具有较好的化学升温效果、去除夹杂物效果同RH精炼炉相当;采用单嘴精炼炉进行20炉超低碳钢合金成分调整结果表明,合金收得率高,硅、锰、铝的收得率分别为93%～96%、93%～95%、64%～67%。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.