Si和Mg元素对铝合金熔体采用细化剂效果的影响

研究Si、Mg元素对Al-Ti-C中间合金细化铝合金晶粒效果的影响，并探讨了其影响机制。结果表明：Si、Mg元素均能促进Al-Ti-C中间合金对铝晶粒的细化作用，一般Si的含量在0．5％时，Al-Ti-C的细化效果最佳；在细化处理温度相同的情况下，Mg的促进作用更明显一些，并且不存在“温度效应”。试验表明，当铝合金中同时存在Si、Mg元素时（6063铝合金），Al-Ti-C的细化效果会更加显著。     

微量Mg、Si对Al-Ti-C中间合金晶粒细化效果的促进作用

研究结果表明：微量的Mg和Si均能促进Al-Ti-C中间合金对工业纯铝和6063合金等铝合金的晶粒细化作用;在细化温度相同的条件下,与Si相比,Mg对Al-Ti-C中间合金细化效果具有更大的促进作用,微量的Mg可以抑制Al-Ti-C中间合金晶粒细化的“温度效应”;铝熔体中同时存在微量的Mg和Si时Al-Ti-C中间合金的细化效果更好,初步探讨了这两种微量元素促进Al-Ti-C中间合金细化效果的机理。     

Al-Ti-C中间合金对Mg-Al合金的晶粒细化作用

制备了一种用于Mg-Al合金晶粒细化的Al-Ti-C中间合金。发现该Al-Ti-C中间合金可以有效地细化镁合金的晶粒，细化后的AZ61合金的抗腐蚀性能大大提高。分析认为，Al-Ti-C中间合金中起晶粒细化作用的是Al4C3和TiC的复合相。     

Al-Ti-C对6063铝合金晶粒细化的影响

研究了Al-Ti-C添加剂对6063铝合金铸态组织的细化作用，结果表明，Al-Ti-C细化剂本身的化学成分及过剩Si元素含量对细化效果均有显著影响。机理分析得知，TiC形核颗粒的稳定性与Ti、Si元素的含量存在密切关系，合理选择铝钛碳的种类、适当调整Si元素的含量均能改善合金的铸态组织。     

Al-Ti-C对6063铝合金晶粒细化的影响与机理分析

从两个方面研究了Al-Ti-C添加剂对6063铝合金铸态组织的细化作用。结果表明，Al-Ti-C细化剂本身的化学成分及铝合金中Si元素含量对细化效果均有显著影响。机理分析表明，TiC形核颗粒的稳定性与Ti,Si元素的含量存在密切关系，合理选择铝钛碳的种类，适当调整Si元素的含量均能改善合金的铸态组织。     

影响Al-Ti-C对铝合金细化效果的因素分析

研究了熔炼温度、合金元素及稀土Ce对Al-Ti-C作用效果的影响,并从理论上分析它们的作用机理.结果表明,熔炼温度在760 ℃时Al-Ti-C的细化效果较为显著;合金元素Si的过剩量对Al-Ti-C的作用效果较为敏感,对于Al-Mg-Si系合金Si元素的含量不宜超过0.5%;适量稀土Ce能合理改善Al-Ti-C中间合金的处理效果,处理后的试样具有较高的伸长率和抗拉强度.     

Mg对Al-Ti-B、Al-Ti-C中间合金细化铝晶粒效果的影响

试验研究了Mg对Al-5Ti-1B和Al-5Ti-0.2C两种中间合金细化铝晶粒效果的影响,分析了Mg影响两种中间合金细化铝晶粒行为的机制。结果表明,在w(Mg)=1%～7%的范围内,镁含量的增加,对两种中间合金细化铝晶粒的促进作用不显著,但对晶粒形貌有显著的影响;晶粒形貌取决于所用中间合金的种类和Mg添加量大小,相同镁含量时,用Al-5Ti-1B细化比用Al-5Ti-0.2C细化后晶粒的树枝化程度小;细化所用的中间合金相同时,随着镁含量的增加,细化晶粒的树枝化程度增大。     

不同加钛方法对6063合金细化的研究

加钛方式不同，钛含量不同，对铝及其合金的晶粒细化效果不同。对比研究了用电解低钛铝合金、加Al—5Ti中间合金、Al—5Ti—1B中间合金及电解低钛铝合金加Al—B中间合金4种加钛方式及不同钛含量对6063合金的晶粒细化效果。研究结果表明：不同的加钛方式对6063合金均有明显的细化效果，随着钛含量增加，晶粒逐渐变细；钛含量相同时，电解加钛的细化效果优于Al—5Ti中间合金的细化效果；当合金中含有硼时，钛含量相同时，电解加钛加Al—B中间合金的细化效果优于加Al—5Ti—1B的细化效果。     

Al-Ti-B合金昌粒细化剂及细化机理的发展与现状

晶粒细化是提高材料强度和塑性,改善铸件质量的重要途径之一,其成功的关键在于形成高效、稳定、价廉的细化剂产品。在介绍Al-Ti-B合金晶粒细化剂的应用现状及生产方法的基础上,分析了晶粒细化剂的细化机理,明确了目前尚存在的问题,指出了今后的发展方向。     

Al—Ti—B晶粒细化剂细化效果的研究

结合铸轧板坯生产实际，简介了不同Ａｌ－Ｔｉ－Ｂ线晶粒细化剂的细化效果及试验过程，指出稀土Ａｌ－Ｔｉ－Ｂ线剂是最经济有效的晶粒细化剂。     

Al-Ti-C中间合金的显微组织与细化性能研究

采用自制的Al-Ti-C中间合金晶粒细化剂,检验其对工业纯铝的细化效果,并通过光学显微镜（OM）、扫描电镜（SEM）和能谱分析（EDS）等手段研究了不同中间合金组织对工业纯铝的细化性能的影响.结果表明,Al-Ti-C细化剂合金组织由α-Al基体,针状或块状TiAl3相及TiC粒子团组成;Al-Ti-C具有优异的细化α-Al晶粒的性能,添加0.2%的Al-Ti-C后工业纯铝开始获得明显的细化效果;Ti/C比对Al-Ti-C组织有重要影响,在纯铝中添加不同组织的Al-Ti-C产生不同的细化效果,其中块状TiAl3的细化性能优于针状TiAl3;在其它工艺条件不变的前提下,选用Ti/C比为8,添加量为0.4%的中间合金,性价比较为理想.     

Grain refinement of primary silicon in hypereutectic Al-Si alloys by different P-containing compounds

The grain refinement behavior of Si-3 P,Si-25 Mn-10 P,and Al-10 Si-2 Fe-3 P master alloys on hypereutectic Al-24 Si alloy was studied.Microstructure analysis indicates that the P-containing compounds in the three master alloys are Si P,Mn P,and Al P,respectively.The coarse flower-like primary silicon in the Al-24 Si alloy transforms into smaller,well-distributed blocks with the addition of various master alloys.When pouring at 840°C,the average grain size of the primary silicon refined by Si-25 Mn-10 P master alloy with a holding time of 30 min is about 18μm,which is significantly smaller than those refined by Si-3 P and Al-10 Si-2 Fe-3 P master alloys.The grain size shows an increasing trend when the holding time is further prolonged.Higher holding temperature has a positive effect on the grain refinement of Si-25 Mn-10 P master alloy.The grain refinement mechanism of the three master alloys was also discussed.     

变形AZ31镁合金的晶粒细化

利用Gleeble-1500D热模拟机，对AZ31镁合金在300～450℃以及应变速率为0．1和1.0s^-1条件下进行了热压缩。发现在热压缩变形过程中发生了动态再结晶，其动态再结晶平均晶粒尺寸(d)的自然对数与ZenerHollomon参数(Z)的自然对数成线性关系。再利用d与Z的关系，通过较低的热挤压温度(300～350℃)，获得了动态再结晶晶粒直径在10～20μm之内的镁合金管材。     

Review of grain refinement methods for as-cast microstructure of magnesium alloy

As the lightest structural metal, Mg and Mg-based alloys have great potential applications in the aerospace, automotive and nuclear industries. However, such applications have been limited by low ductility and strength. Theoretically, small grain sized structure can synchronously improve its ductility and strength. Yet,universally reliable grain refinement techniques for the magnesium alloys are still under investigation and some are in strong debating. This paper presents a brief review of development of grain refinement methods for magnesium alloys, which would contribute to a better understanding of the factors controlling grain refinement and provide an outlook of future research in this field.     

Effect of A1P master alloy on grain refinement of primary silicon in eutectic Al-Si alloys

To obtain the finer primary silicon crystals, the proprietary Al-P master alloy was adopted to modify the eutectic Al-Si alloys and the most suitable modification process was made in the experiments. The SEM (Scanning Electron Microscope) and DSC (Differential Scanning Calorimeter) analysis indicate that the Al-P modifier has more advantages over Cu-P and Fe-P modifier in easily addition, no elemental alteration and less undercooling of primary silicon's solidification, which suggests the Al-P master alloy is an effective modifier of eutectic Al-Si alloys.     

Effects of various Mg-Sr master alloys on microstructural refinement of ZK60 magnesium alloy

The effects of various Mg-Sr master alloys(conventional as-cast,rapidly-solidified,rolled and solutionized) on microstructural refinement of ZK60 magnesium alloy were investigated.The results indicate that the refinement efficiency of various Mg-Sr master alloys in ZK60 alloy is different.The rolled Mg-Srmaster alloy is found to have relatively higher refinement efficiency than the conventional as-cast,solutionized and rapidly-solidified Mg-Sr master alloys.After being treated with the rolled Mg-Sr maste...