Grain refinement in magnesium alloys by aging-rolling-aging method and by rolling in two phase region.

通过时效-轧制-时效法和两相区轧制细化镁合金晶粒。

• 批准号: 14350373
• 负责人: YAMAMOTO Atsushi
• 金额: $ 9.41万
• 依托单位: University of Hyogo (2004)Himeji Institute of Technology (2002-2003)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14350373/
• 关键词: magnesium alloy; grain refining; recrystallization; aging; rolling; sever deformation; 集合組織制御; 温間加工; 曲げプレス加工; 加工熱処理; 析出物; 晶出物

A new technique for preparing magnesium alloys having fine grained microstructures has been developed. Severe deformation and aging method can lead to such materials, but, for example, ECAP method, extrusion with high extrusion ratios or multi axes forging could not be applied to materials with large scales. Foil metallurgy may be applied to sheet materials, but it is not appropriate for continuous production. Simple rolling and aging method seems to have advantages in large scale application and continuous production. Mechanism of the grain refining in this method is based on dynamic recrystallization.Therefore, recrystallization in high purity magnesium was firstly investigated. Specimens of pure magnesium of about 10 x 10 mm^2 and 0.8 mm in thickness were cold rolled at room temperature with various reduction rates up to 80 %. Transmission electron microscopic(TEM) observations showed that recrystallization occurred in cold-rolled at about 30%, and in the specimen cold-rolled at abo … More ut 80%, recrystallization occurred in a large area of the specimen. Burgers vector analyses of dislocations in the specimen showed that non-basal slip system was operated even at room temperature. Magnesium has an intrinsic property for easily recrystallizing. However, in the case of pure magnesium, grain growth of recrystallized grains occurs.Precipitates were seemed to be effective to suppress the grain growth. Magnesium-lithium-zinc alloys were solution heat treated, aged and then hot-rolled at the temperature range corresponding to two phase (α+β) region, which lead to grain refining in both the α and β grains. However, Mg-Li-Zn alloys are not generally used for engineering materials. Therefore, the same process composed of rolling and aging was applied to AZ31B and AZ91E magnesium alloys. On the AZ31B alloy, grain size was decreased from about 50 to 100 μm in solution heat treated condition to about 3 to 5 μm after the treatment. While on the AZ91E alloy, which was as cast alloy, grain size was decreased from about 200 μm into 20 μm in diameter.Grain refining on engineering Mg alloys was successfully carried out as mentioned above, however, textures of the alloys showed that the basal plane was perpendicular to the specimen surface, the general texture of magnesium alloy sheets. In order to accomplish both the fine-grained microstructures and non-basal textures, we have newly developed another method, that is, the sheet specimen was hot-pressed to be formed a wavy shape, the pressing was repeated with rotating the specimen at 45 degrees for 15 to 18 times. The aim has been successfully achieved by the method. Less

已经开发了一种用于制备具有细粒微结构的镁合金的新技术。严重的变形和老化方法可以导致这种材料，但是，例如，ECAP方法，具有高延伸比或多轴锻造的延伸不能应用于具有较大尺度的材料。箔冶金可以应用于板材材料，但不适用于连续生产。简单的滚动和老化方法似乎在大规模应用和连续生产中具有优势。在此方法中，晶粒精炼的机理基于动态重结晶。因此，首先研究了高纯度镁的重结晶。在室温下冷滚冷约10 x 10 mm^2和0.8毫米的纯镁样本，不同的降低速率高达80％。透射电子显微镜（TEM）观察结果表明，冷卷中的重结晶发生在约30％，并且在ABO冷卷的样品中……更多的UT 80％，重结晶发生在大面积的样本中。汉堡矢量分析标本中的位错方面表明，即使在室温下，非基质滑移系统也可以运行。镁具有易于重结晶的内在特性。然而，在纯镁的情况下，发生重结晶的谷物生长。预测似乎有效抑制谷物的生长。镁锌合金是溶液进行热处理，老化然后在对应于两个相（α+β）区域的温度范围内热卷的，这导致α和β晶粒的晶粒精炼。但是，MG-LI-ZN合金通常不用于工程材料。因此，将滚动和衰老组成的相同过程应用于AZ31B和AZ91E镁合金。在AZ31b合金上，在治疗后，在溶液热处理条件下，晶粒尺寸从大约50μm减少到约3至5μm。虽然在AZ91E合金上以铸造合金为单位，但晶粒尺寸从大约200μm提高到直径为20μm。晶体成功地进行了工程米格合金的精炼，如上所述，合金的质地表明，基本平面的基本平面垂直于标本表面，标本表面是一般质地Alloy Shees。为了完成细粒度的微观结构和非基质纹理，我们是新开发的另一种方法，即，薄板样品被热粘以形成波浪形，并以45度的45度旋转样品重复进行15至18次。该方法成功实现了目标。较少的

项目成果

Grain refinement in AZ91E magnesium alloy by thermo-mechanical treatment

形变热处理细化AZ91E镁合金晶粒

• 发表时间: 2004
• 期刊: Mater.Sci.Forum 475-479
• 作者: A.Yamamoto;M.Ikeda;H.Tsubakino
• 通讯作者: H.Tsubakino

Grain refinement on AZ31 magnesium alloy by highly strained and annealed method

高应变退火法细化AZ31镁合金晶粒

• 发表时间: 2004
• 期刊: Mater.Sci.Forum 449-452
• 作者: A.Yamamoto;M.Kakishiro;M.Ikeda;H.Tsubakino
• 通讯作者: H.Tsubakino

Plastic deformation on high purity magnesium prepared by deposition coating technique

沉积涂层技术制备高纯镁的塑性变形

• 发表时间: 2005
• 期刊: Mater.Sci.Forum 488-489
• 作者: A.Yamamoto;M.Jotoku;H.Tsubakino
• 通讯作者: H.Tsubakino

A.Yamamoto, T.Ashida, Y.Kouta, B.Kim, S.Fukumoto, H.Tsubakino: "Precipition in Mg-(4-13)% Li-(4-5)% Zn tenary Alloys"Mater.Trans.. 44(in press). (2003)

A.山本、%20T.芦田、%20Y.Kouta、%20B.Kim、%20S.福本、%20H.Tsubakino:%20"降水量%20in%20Mg-(4-13)%%20Li-(4-

Plastic deformation on high purity magnesium prepared by deposition technique

沉积技术制备高纯镁的塑性变形

• 发表时间: 2005
• 期刊: Mater. Sci. Forum 488-489
• 作者: A. Yamamoto;M. Jotoku and H. Tsubakino
• 通讯作者: M. Jotoku and H. Tsubakino