5086铝合金冷轧板的退火工艺研究

选择变形量为38.5%的5086铝合金冷轧板,研究了退火温度分别为180、200、220、240、260、280℃,保温时间为0.5、1、2、4 h的退火工艺。结果表明,变形量为38.5%的冷轧5086铝合金板,当退火温度超过240℃,保温时间超过2 h后,屈服、抗拉强度下降,伸长率增加;当退火温度超过220℃时,合金的晶间腐蚀性能改变明显。当退火温度为220~240℃和保温时间为2~4 h时,综合性能达到较优。     

均匀化处理对5083铝合金铸锭组织与性能的影响

通过常温拉伸试验、硬度检测、电导率检测以及扫描电镜金相分析,对比分析不同工艺均匀化处理后5083铝合金铸锭的组织与性能,发现不同均匀化热处理工艺对铸锭的微观组织与性能有显著的影响。研究结果表明,通过420  ℃×2 h→510 ℃×10 h的双级均匀化处理后,合金获得最优的微观组织与综合力学性能。     

Cr含量对5083高镁铝合金组织和性能的影响

研究了添加w(Cr)=0. 06%～0. 24%对5083铝合金铸锭均匀化组织、冷变形组织、拉伸性能、断口形貌的影响。结果表明:随着Cr含量的增加,5083铝合金强度提高,塑性降低,相应的拉伸试样断口形貌由韧性断裂到出现局部脆性断裂。当添加w(Cr)=0. 19%时,5083铝合金中出现粗大的Al-Mn-Cr-Ti-V金属间化合物相,粗大的化合物相在轧制过程中破碎,沿轧制方向分布,恶化合金的塑性和成形性能。     

Electrochemical performance of Gd-Co-Mn alloys

The Gd-Co-Mn alloys with compositions of Gd33.3Co66.7,Gd33.3Mn66.7,Gd22.2Co74.8Mn3 and Gd25Co70Mn5 were prepared and examined by X-ray diffractometer.The electrochemical properties of these alloys such as discharge capacity,cycling performance and high rate dischargeability were investigated by battery testing instruments in alkaline electrolyte.The discharge capacity of Gd22.2Co74.8Mn3 was the highest among these alloys at the same discharge current density,and the maximum value was 376.7 mAh/g discharged at 150 mA/g.The discharge capacities of the alloys Gd33.3Co66.7 and Gd33.3Mn66.7 reached their maxima(about 225 and 325 mAh/g)at discharge current density of 150 mA/g.A comparison of the electrochemical performance of the Gd-Co-Mn alloys revealed that the alloy Gd22.2Co74.8Mn3 possessed better electrochemical performance and had better discharge capacity,cycle stability,while the alloy Gd25Co70Mn5 had a better high rate discharge ability.In general,the electrochemical performance of ternary alloys was better than binary alloys in this case.     

退火温度对3003铝合金板材组织和性能的影响

对3003铝合金板材不同温度退火后,进行硬度、拉伸、杯突等力学性能检测,并通过EBSD观察其微观组织变化。结果表明,随着退火温度的升高,硬度和拉伸强度逐渐降低,伸长率和杯突值逐渐升高;480℃保温3 h退火,其强度、硬度和杯突深度趋于稳定,伸长率达到最大值。     

双级时效对6082型材性能的影响

通过硬度、电导率、力学性能、金相显微镜、扫描电镜等研究固溶淬火后双级人工时效对6082挤压型材的影响。结果表明,6082挤压组织中包括了少量的Mg2Si和α-(AlMnFeSi)相,但经固溶处理后Mg2Si相会慢慢回溶到铝基体,而α-(AlMnFeSi)相很难溶解。6082带筋板型材经540℃×60min固溶,双级人工时效120℃×10min+175℃×4h后,力学性能为抗拉强度333MPa,屈服强度310MPa,A50=9.5%,而540℃×60 min固溶+175℃×8 h时效后的力学性能为:抗拉强度328MPa,屈服强度309MPa,A50=8.9%。     

退火温度对船用Al-Mg-Mn-Cr合金组织和性能的影响

通过力学性能测试、光学显微镜及腐蚀性能测试等手段,研究了不同退火温度对实际生产的5AN6铝合金板材组织和性能的影响。结果显示:合金在退火后力学性能持续下降,于280 ℃退火时强度发生大幅度下降;在300~360 ℃退火时,合金力学性能趋于稳定;原始状态合金的晶粒组织为不完全的纤维组织,在280 ℃退火之后晶粒明显细化,可认为合金在280 ℃退火后发生了再结晶;5AN6铝合金的腐蚀性能温度敏感区间为160~240 ℃,在此温度区间内显微组织显示为沿晶界连续析出的β相。     

高镁铝合金板材MIG焊接头组织性能分析

采用国产5087焊丝熔化极惰性气体保护焊(MIG)对20 mm厚5083铝合金板材进行焊接试验,借助成分分析仪、光学显微镜、维氏硬度计以及材料试验机,对焊后材料显微组织特征与材料性能研究。试验结果表明,焊丝满足焊接需求;维氏硬度值在80～90 HV之间,其中焊核区硬度最低;焊接板各区显微组织差异明显,符合热影响的作用效果;焊接接头具有较好的力学性能,焊后抗拉强度与焊前母材抗拉强度之比(焊接强度系数)均大于0. 9。     

Isothermal section of Nd-Zr-Si ternary system at 773 K

Phase diagram is an important basis for materials research and materials application.The phase relations of the Nd-Zr-Si ternary system at 773 K were investigated by X-ray powder diffraction analysis,metallographic analysis and scanning electron microscopy with en-ergy dispersive analysis.The isothermal section of the phase diagram of the Nd-Zr-Si ternary system at 773 K was determined.The isother-mal section of the system consisted of 13 single-phase regions,23 two-phase regions and 11 three-phase regions.The homogeneity range of α-NdSix was from 63 at.% to 66 at.% Si(with x=1.70-1.94).The maximum solid solubilities of Nd in Zr-Si binary compounds and Zr in the Nd-Si binary compounds were observed less than 1 at.% at 773 K.     

5454铝合金冷轧板的退火工艺

通过力学性能测试和显微组织观察,对比分析了经不同温度(60~600℃)退火的5454铝合金冷轧板的力学性能和显微组织变化规律。研究表明:对于5454铝合金冷轧板,退火温度120℃为稳定化退火阶段,120~270℃为回复处理阶段,270~330℃为再结晶阶段,360~570℃为再结晶长大阶段,600℃时晶粒球化长大,发生过烧;最佳的O态退火温度为330℃。