技术信息

齐齐哈尔钢厂于1990年从瑞典引进45t高功率低位出钢槽电弧炉,经改造后已造成我国第一台自行设计,自己制造结构简单,全部采用国产化的高功率偏心底(EBT)出钢电弧炉。工艺流程: 装料→熔氧→吹氧→泡沫渣→C.P.温度合适→出钢→留钢留渣操作→包中加入脱硫剂→全封闭式出钢→电子称控制出钢量→精炼→加热→取样。测温→微调合金→加热→全程吹氩→镇静→浇     

20CrMoH高质量齿轮钢的工艺实践

简述了淮钢20CrMoH高质量齿轮钢的工艺,介绍了高炉铁水→转炉→LF精炼→RH处理→方坯连铸→连轧长流程生产路线的工艺特点,通过采用核心技术,保证了20CrMoH齿轮钢质量.     

窄淬透性带齿轮钢生产试验研究

齿轮钢20CrMnTiH的淬透性窄带化，是用户对20CrMnTiH钢的新要求。根据冶炼设备条件，进行了电炉→LF－VD→模注冶炼窄淬透性带齿轮钢20CrMnTiH的试验研究。结果表明，通过窄化钢的化学成分，电炉→LF→VD模注冶炼20CrMnTiH钢工艺可以实现淬透性窄化，钢的各项性能符合用户要求。     

高档热轧耐磨钢球用钢B2的研制与开发

通过分析高档热轧耐磨钢球的使用条件,提出了高档热轧耐磨钢球用钢B2的技术要求,研究了EAF→LF→VD→连铸→加热→轧制生产B2钢的工艺措施。研发的高档热轧耐磨钢球用钢B2各项指标检验均符合客户要求,并成功通过用户试用打入国际市场。     

天钢开发Z向钢的生产实践

通过对天津钢铁集团有限公司开发与试验Z向钢生产过程数据整理与分析,总结了生产Z向钢过程中,严格控制钢中的NnS、钢中的H和保证良好的铸坯质量等控制关键点,同时提出了适合天钢现行设备条件下生产Z向钢的工艺改进措施,确定工艺路线为铁水→转炉→LF炉→板坯连铸→堆冷→轧钢。开发试制的Z相钢性能全部满足GB／T5313—1985厚度方向性能钢板标准要求,Z向断面收缩率平均值为65．8％,产品质量优良。     

济钢预硬型塑料模具钢的研制开发

要针对模具钢的市场需求,采用KR铁水预处理→120t转炉冶炼→脱氧合金化→CAS精炼→LF精炼→VD真空处理→板坯连铸→热装炉→轧制→钢板切割→自然冷却→回火工艺,研制开发了J30预硬型塑料模具钢,并对试验结果进行了全面的分析,钢的化学成分稳定,钢板表面硬度均匀,Ⅰ级探伤全部合格。     

RH炉控制工艺的优化及效果

通常钢厂生产品种钢工艺流程为：铁水预处理→转炉→LF及钙处理→RH→浇铸。在上述工艺流程的基础上,对RH炉控制进行了新工艺研究,为冶炼高级别品种钢创造条件。     

高碳磨球钢生产工艺实践

对高碳磨球钢的生产工艺技术进行试验研究,采用转炉→LF→RH→连铸→收集→缓冷→加热→水除磷→开坯→连轧的生产工艺路线制造高碳磨球钢,成品质量检测结果表明:钢中化学成分控制准确,碳偏析、低倍组织等其他相应技术指标均满足要求,非金属夹杂物相对比较细小。     

Q460E超声探伤缺陷的分析和工艺改进

南钢采用原辅料验收→铁水预处理→配料→转炉冶炼→LF精炼→RH精炼→连铸→铸坯检验→步进式加热炉→4700轧机轧制的工艺路线生产Q460E钢,经超声波探伤发现,部分钢板存在探伤不合格的情况。通过对探伤不合格的缺陷部位扫查定位,并取试样进行金相、扫描电镜分析,最终确认了连铸机的拉坯速度快、RH钢液真空循环脱气的时间短,是造成该Q460钢探伤不合格的主要原因,并提出了相应的改进措施。     

高档轿车齿轮用钢20CrNi2MoSH的研制

本钢采用EBT→LF→VD→连铸235mm×265mm方坯→缓冷→加热→棒材连轧机组→缓冷→精整→检验→包装缴库→发货的工艺流程,成功研制生产了高档轿车齿轮用钢20Cr Ni2Mo SH。产品化学成分均匀,有害元素及气体含量低,末端淬透性稳定,钢材组织均匀,纯净度高,致密度好,满足了高档轿车齿轮用钢的使用要求。     

Transfer between contextual conditional discriminations: An examination of how stimulus conjunctions are represented.

In 2 experiments, when rats were placed in 1 pair of contexts, A and B, 2 relationships were in force (X→food and Y→no food), and when they were placed in another pair of contexts, C and D, the complementary relationships were operative (Y→food and X→no food). In Experiment 1, rats then received a 2nd discrimination that was either contextually congruent (in A and B, Y→food and X→no food; in C and D, X→food and Y→no food) or contextually incongruent (in A and D, Y→food and X→no food; in C and B, X→food and Y→no food) with the 1st discrimination. In Experiment 2, the 1st discrimination, involving X and Y, was interleaved with a 2nd discrimination, involving V and W, that was again either congruent (in A and B, V→food and W→no food) or incongruent (in A and D, V→food and W→no food) with the 1st discrimination. The congruent discriminations were acquired more readily than were the incongruent discriminations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are operators describing b→sγ？

The operators of b→ sγ, b →sl＋l- are usually regarded as being sufficient to describe b →sγγ, b → sl＋l-T with the statement that contributions from diagrams without an effective vertex b --＊ ST to processes b →sγγ and b →sl＋l-T are negligible. In this wor     

铂钯精矿提纯工艺与产业化设计

根据某铜冶炼企业铂钯精矿的特点,钯提纯工艺设计为"洗矿→盐酸酸浸除杂→氯化浸出→亚硫酸钠还原金→铂钯沉淀→铂钯分离→钯还原",铂提纯工艺设计为"氯铂酸铵还原→氯化浸出→氯化铵沉铂→煅烧",并进行提纯工艺匹配设备选型与产业化设计,在生产实践基础上进行经济效益简析。结果表明,铂、钯回收率分别为95.0%、98.5%以上,年可回收12.0 kg铂粉、107.6 kg钯粉,年增加收益达6 158万元,年投资成本约67万元,项目经济效益显著。     

Learning about associations: Evidence for a hierarchical account of occasion setting.

In 2 experiments rats were trained on a switching discrimination, with 4 occasion setters, A, B, C, and D and 2 target stimuli, x and y. When signaled either by A or by B, x was reinforced with food and y was not, whereas when signaled either by C or by D these reinforcement relations were reversed (i.e., A: → x+, A: y → ?, B: x → +, B: y → ?, C: x → ?, C: y → +, D: x → ?, D: y → +). In a subsequent Stage A was paired with shock, and then the degree to which food–reinforced (Experiment 1a) and nonreinforced (Experiment 1b) presentations of x and y were capable of eliciting fear was assessed. Those conditioned stimulus (CS)/unconditioned stimulus (US) relations that had been operative in the presence of the fear-eliciting occasion setter A (i.e., x → +, y → ?) elicited more fear than the alternative CS/US combinations (i.e., x → ?, y → +). The implications of these findings are discussed with reference to theories of occasion setting and of configural learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of the steel AISI 4145HM for senior petroleum drill of BX Steel

The Steel AISI 4145HM for senior petroleum drill of BX Steel was produced by the follow sheet: hot metal pretreatment→converter→LF→RH→caster 350 mm×470 mm rectangular billet→hot delivery→reheating→800 mill rolling→insulation→straightening→anneal→grinding→inspection→packaging and pay into treasury→shipment.Selected BX Steel particular hor metal,adopted hot metal desulphurization pretreatment technology.The LF refining making the white slag,and keep a certain time.The RH treatment must make sure the vacuum degree and refining time,more importantly controlling argon blowing process.In addition,must design proper technology data continuous casting similar superheat,casting speed,and specific water flow rate.Depend on technological measures,the product been had series of the qualities:homogeneity of chemical composition,low content of harmful elements,high purity,compact organization.Adopted the process of casting billet hot delivery and hot charging,used stepping heating furnace,and designing reasonable thermal parameters.Two -high reversing mill rough rolls preparation square billet,short - stress - path rolling mill rolls round bar.Steel products bad holding and controlling soaking time and temperature. Steel products bad annealed,and annealing process must been controlled for ensuring steel hardness uniform. For avoiding residual stress,steel been straightened before anneal.The test results and using effect shows that the producing with uniform annealing hardness and nice processing properties,nice overall mechanical properties,were recognized by users.     

大规格轴承钢GCr15SiMn的试制开发

莱钢特钢事业部采用热装铁水+废钢→100 t电炉冶炼→LF精炼→VD真空脱气→连铸(Φ500 mm)→入坑缓冷→加热→Φ1350×1+Φ950×4+Φ800×2轧制→入坑缓冷→精整的工艺流程生产Φ120 mm GCr15Si Mn轴承钢,通过优化冶炼工艺、保护浇注、弱二冷、控制加热、大压缩比轧制等措施,开发的GCr15Si Mn轴承钢成分均匀,纯净度高,氧含量控制在(9~10)×10-6,碳化物带状级别均在1.5以下,液析0.5级,各项指标完全达到技术标准要求。     

钛、钨氧化物碳热还原-碳化的热力学和热分析

为了研究采用TiO₂、WO_2.72和炭黑粉末为原料,在惰性气氛下通过碳热还原-碳化制备(Ti,W)C固溶体的过程机理,采用HSC Chemistry热力学分析软件、热重和差示扫描量热分析方法,对物相的演变过程进行分析。结果表明,因球磨导致原料反应活性升高、气-固反应共存等,实际的反应起始温度低于热力学计算值。随温度升高,TiO₂和WO_2.72分别按TiO₂→Ti₄O₇→Ti₃O₅→Ti2O₃→TiO→TiC和WO_2.72→WO₂→W→W₂C→WC的转变顺序被还原并碳化。为了加速反应的动力学进程,通过碳热还原-碳化制备(Ti,W)C固溶体的最终温度应在1400℃以上。     

Representation of serial order in pigeons (Columba livia).

In Experiment 1, 2 groups of pigeons were trained to respond to either a 4-item (A→B→C→D) or 5-item (A→B→C→D→E) list. After learning their respective list, half of the subjects were trained on a positive pair with reinforcement provided when pairs were responded to in the order true to that of the original sequence (4-item: B→C; 5-item: B→D). The remaining subjects were trained on a negative pair with reinforcement provided for responding to the pairs in the order opposite to that learned in the original sequence (4-item: C→B; 5-item: D→B). Subjects in the positive pair condition learned their respective pair faster than did subjects in the negative pair condition. In Experiment 2, after reaching criterion on a 4-item list, subjects received 16 BC probe trials spread across 4 sessions of training. Subjects performed significantly above chance on the probe trials. The performance of our subjects in Experiments 1 and 2 demonstrates that, similar to monkeys, pigeons form a representation of the lists that they learn. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comment on phase conventions in helicity formalism

Using the sequential decay process e ＋ e- → J/ψ→ΛΛ, Λ→ pπ- , Λ→ pπ＋ as an example, the procedure for deducing the full angular distribution is illustrated by adopting both the Jacob-Wick and Jackson conventions in the helicity formalism. To make sure that