钎焊式空冷系统用嵌入式冷轧铝-钢复合带材的开发

通过"表面处理+冷轧复合+退火处理"三步法,即先采用钢丝刷对4 mm 08Al钢(/%:0.01C,0.018Al)和0.23 mm 4A60铝带表面进行处理,然后在前张力30 kN下利用高精度Φ420 mm四辊轧机对铝-钢进行60%的单道次冷轧复合,并于罩式退火炉进行520℃24 h的退火处理,开发出了极薄复层(80~90μm)冷轧4A60铝/08Al钢1.7 mm复合带材。复合带材中08Al钢的组织为平均晶粒尺寸15μm的等轴铁素体,抗拉强度≥320MPa,伸长率≥28%,弯曲性能也符合指标要求。复合带材在(600±10)℃钎焊后铝钢界面未发现金属间化合物,铝钢界面未发现分层现象。     

冷轧复合材料的复合工艺实验

 进行了钢 铜、钢 铝冷轧复合实验，即表面处理+复合轧制+轧后热处理。结果表明，复合轧制前，必须对基材和复合材料进行表面清洗，基材钢需进行表面毛化处理，要求表面粗糙度为Rz=81~101 μm，较薄的复合材料如铜、铝可不经毛化处理直接复合轧制。钢 铝无张力复合轧制所需总相对压下量为40%≤ε≤60%，钢 铜无张力复合轧制所需的总相对压下量为ε≥70%。应严格控制热处理的退火温度和保温时间，保温时间过长，会削弱复合面的强度；钢 铝退火温度控制在320 ℃左右，保温时间约1 h；钢 铜退火温度在550~600 ℃范围内，保温时间约15 h。研究认为复合轧制过程中，带材之间的相对跑偏、厚度比控制是亟待解决的问题。     

叠轧Ti/Al复合板结构与力学性能研究

在室温条件下,通过叠轧方法制备了Ti/Al 7层复合板,并在不同温度下进行了退火处理。采用光学显微镜(OM)观察了复合板界面的连接质量,利用扫描电镜(SEM)研究了不同退火温度下复合板Ti/Al界面处的元素扩散行为,并通过拉伸试验研究了原始板材与复合板的力学性能。研究结果表明,轧制压下量对板材变形均匀性及界面结构影响显著,当轧制压下量为60%时,复合板结合质量良好,层状结构完整。当轧制压下量为70%时,Ti层局部产生开裂,使两侧铝层相连,不能保持层状结构。随着退火温度的升高,Ti/Al界面处Ti,Al元素扩散距离增加,Al元素扩散距离大于Ti元素的扩散距离,并有少量的第二相生成。Ti/Al复合板的屈服强度介于原始钛板与原始铝板屈服强度之间,高于混合定律计算值,延伸率低于原始板材,并且随着应变速率的增加,复合板材屈服强度及抗拉强度提高。     

复合带材冷轧变形行为的上限法分析

 应用上限法对双金属复合带材冷轧时厚度、速度变化与轧制力、能量间的关系进行了分析讨论，建立了复合带材冷轧塑性变形行为的数学模型，在此基础上给出了复合带材的强度计算公式。应用这些公式对铝 钢复合带材的强度进行了计算，计算结果与试验结果吻合较好。     

电缆用铜/铝复合带制备工艺研究

研究了制备工艺对电缆用铜/铝复合带组织和性能的影响.结果表明：电缆用铜/铝复合带冷轧复合加工率应大于67%,合理的退火工艺为310℃×1.5h.铜/铝复合界面是通过轧制物理结合-退火冶金结合机理形成的.     

电缆用铜/铝复合带制备工艺研究

研究了制备工艺对电缆用铜/铝复合带组织和性能的影响.结果表明:电缆用铜/铝复合带冷轧复合加工率应大于67%,合理的退火工艺为310℃×1.5h.铜/铝复合界面是通过轧制物理结合-退火冶金结合机理形成的.     

钢和铝异温轧制复合机理的研究

研究异温轧制复合工艺制度对钢和铝复合板初结合强度的影响，结果表明，轧制变形程度和铝层加热温度都是影响复合板初结合强度的主要因素，利用扫描电镜观察分析复合界面形貌，并对微区成分分析证明，异温轧制复合有不同于室温固相复合的结合机制。     

H13钢Φ130 ~ 150 mm热轧材探伤不合格原因分析及改进措施

从H13钢和H11钢Φ130～150 mm热轧材的化学成分、生产工艺及探伤合格率的对比分析得出,平均V含量从0.5%提高到1.0%是导致探伤不合格的关键性因素。根据缺陷分析结果并结合Φ380 mm连铸圆坯低倍组织,得出导致H13钢探伤合格率低的原因是连铸坯中心缩孔在轧制过程中未焊合。通过改进连铸工艺和轧制开坯工艺,将拉速从0.58 m/min提高至0.65 m/min, S-EMS从650 A/5 Hz改进为200 A/8 Hz,开坯增加6,8,9道次压下量从原～60 mm至70～85 mm,将Φ380 mm坯型更改为Φ500 mm,使Φ130 mm H13钢探伤合格率从原来50%左右提升至99.8%,Φ150 mm H13钢探伤合格率从原来15.5%提升至97.2%。     

复合板轧制界面周期性波动的模拟与试验

 为了探究复合板轧后复合界面产生周期性厚度波动的机理和影响因素,基于商用有限元分析软件ABAQUS建立了铝/钢/铝三层对称复合板轧制的有限元模型。通过对轧制过程复合板各层应力变化规律的分析,表明在铝/钢/铝复合板轧制过程,钢层和铝层存在明显的变形不协调现象,铝层的变形趋势明显大于钢层,导致钢层在轧制方向产生拉应力并使钢层发生厚度减薄。同时厚度减薄的发生改变了周围区域的应力分布,使厚度波动呈现周期性特征,通过实验室的轧制试验验证了模拟和分析结果的正确性。     

一种汽车冷凝器翅片用铝合金钎焊复合箔的制备方法

<正>中国专利CN105666052A本发明公开了一种汽车冷凝器翅片用铝合金钎焊复合箔的制备方法,具体包括:芯层Al-Mn合金的制备;钎焊包覆层AlSi合金的制备;按Al-Si/Al-Mn/Al-Si组合进行复合轧制。通过低温热轧的工艺技术、不添加晶粒细化剂,使复合箔芯材Al-Mn合金的原始晶粒粗大化,经过轧制变形后可形成粗大长条形状的晶粒组织。由于大角度晶界的存在,可减少焊接后钎焊包覆     

Chinalco Signed Framework Agreement for Strategic Cooperation with Harbin Municipal Government

正Last month,Chinalco signed framework agreement for strategic cooperation with Harbin Municipal Government in Harbin Xiong Weiping,Chairman of Chinalco,said that based on the strategic deployment to build world top-class mining company with the highest growth potential,Chinalco was now concentrating all efforts on making strategic transition and structural adjustment,strategic cooperation with the local governments where     

Jiangxi Promotes Jiangxi Copper Corporation To Become The World's Most Competitive Mining Company

<正>According to the latest info from Jiangxi Province State-owned Assets Supervision and Administration Commission,Jiangxi Copper Corporation was approved to become the first pilot enterprise for deepening reform.Contents of the pilot work is"Three Self"(self expansion,self decision-making,self     

Journal of Rare Earths Contents List of Vol.32(2014)

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Contributions to Baosteel Technical Research wanted

正Baosteel Technical Research,a quarterly journal,which is issued domestically and abroad,is run and sponsored by Baosteel Group Corporation.Baosteel Technical Research mainly reports the achievements in technological innovation,academic research,new product development and industrial equipment improvement by Baosteel.It will continue to follow up on hot topics and serve the company’s technological development and progress.Its readers include experts in     

Ministry of Industry and Information Technology: No Short Term Solution For Our Country’s Excess Nonferrous Metal Smelting Capacity

【正】According to the Ministry of Industry and Information Technology,the Ministry has released the 2013 Operation Report on China’s Industrial Communication Indu...     

Chinalco Signed Framework Agreement for Strategic Cooperation with Gansu Province

正Recently,Chinalco and Gansu Provincial People’s Government signed"Framework Agreement for Strategic Cooperation on Reform,Restructuring and Transition Development of Chinalco’s Electrolytic Aluminum Enterprises in Gansu",signifying that the strategic cooperation between Chinalco and Gansu Province had made new substantive progress.     

Unavoidable Economic Cycle:30% Of Nonferrous Metal Companies Were Involved In Restructuring

正Owing to continual downturn in real estate and bulk commodity markets,a number of traditional industries in China suffered unfavorable impact in performance.With the progressive disclosure of third quarter report,the no-pleasant-surprise performance of     

Baotou Rare Earth Became the World's Biggest High Performance Magnetic Material Base

正The High Performance Magnetic Material Phase II Project,an industry upgrading project implemented by Inner Mongolia Baotou IronSteel Rare Earth(Group)Hi-tech Co.,Ltd,recently basically finished equipment commissioning,signifying that the enterprise had developed the production capacity of15000 t/a Nd-Fe-B strip casting alloy and 5000t/a Nd-Fe-B magnet,thus becoming the world’s     

Introducing Two Central Enterprises to Integrate Rare Earth Industry,Shandong Rare Earth Group Breaks Surface

正With the signing of"Letter of intention for Propelling Integration of Shandong Rare Earth Enterprises"between Shandong Province Commission Of Economy and Informatization,China IronSteel Research Institute Group("China Steel Institute"),and China Rare MetalsRare Earth Co.,Ltd("China Rare Earth"),the"Shandong Rare Earth Group"jointly set up by the 3 units thus broke surface.On August 9,reporters of the China Economic Herald learned from Shandong Province     

Aluminium Production by Province or City in 2014

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