Influence of Gravity on Solidified Micro-structuire.

重力对凝固微观结构的影响。

• 批准号: 14350403
• 负责人: NAKAE Hideo
• 金额: $ 9.66万
• 依托单位: School of Science and Engineering, Waseda Univ.
• 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-14350403/
• 关键词: Solidification structure; convection; zero gravity; solid; liquid interface; gravity segregation; freckle

The influence of gravity on the solidification of monotectic or eutectic alloys has been investigated under microgravity environments. However, in most of the previous experiments, e.g., in free fall systems, in aircraft or in space laboratories, the growth rate was too high to realize the planar solid/liquid interface. This is due to the limitation of the time for solidification. In order to study the influence of gravity on the microstructure of directionally solidified Al-In monotectic alloy, Ag-Si and Al-Si eutectic alloys, and Ni base-super alloy both the downward and upward unidirectional solidifications(U.D.S.) were carried out. In the case of the downward U.D.S. by the current Bridgman method, This causes a shrinkage cavity at the solid/liquid interface during solidification.(1)Regarding the unidirectional solidifications of Al-In alloy, the Monotectic L_2 phase grows continuously in both growth directions. However, the morphology in the downward U.D.S. shows a tendency to form a so-called "banded structure."(2)In the case of the upward U.D.S. of the Ag-Si alloy, the eutectic Si phase grows continuously and its morphology shows the typical faceted/non-faceted eutectic structure. On the other hand, in the case of the downward U.D.S., the eutectic Si phase grows discontinuously and disperses in the α-Ag phase with a diameter of several micrometers.(3)The eutectic Si phase of the Al-Si grows continuously regardless of the growth direction. There is no morphological difference between the upward and the downward U.D.S. specimens.(4)The formation of freckle structure is greatly affected by the Solidification direction. This means that the formation of freckle structure is controlled with the convection due to the gravity.

在微重力环境下，研究了重力对偏晶或共晶合金凝固的影响。然而，在以往的大多数实验中，例如在自由落体系统中、在飞行器中或在空间实验室中，生长速率太高，无法实现平面固/液界面。这是由于固化时间的限制。为了研究重力对定向凝固Al-In偏晶合金、Ag-Si和Al-Si共晶合金以及镍基高温合金向下和向上定向凝固组织的影响。都被执行了。在目前Bridgman法下拉深的情况下，这会在凝固过程中在固/液界面产生缩孔。(1)Al-In合金定向凝固时，偏晶L_2相在两个生长方向上都是连续生长的。(2)当合金向上生长时，共晶Si相不断长大，并呈现典型的多面/非多面共晶组织。另一方面，在向下生长的情况下，共晶Si相不连续生长，弥散分布在直径为几个微米的α-Ag相中。(3)无论生长方向如何，Al-Si中的共晶Si相都是连续生长的。向上和向下的UDS试件之间没有形态上的差异。(4)凝固方向对雀斑结构的形成有很大影响。这意味着斑点结构的形成受控于重力引起的对流。

项目成果

過共晶片状黒鉛鋳鉄の減衰特性に及ぼす黒鉛形状とマトリックスの影響

石墨形状和基体对过共晶片状石墨铸铁阻尼性能的影响

• 发表时间: 2004
• 期刊: 鋳造工学 76
• 作者: 趙 柏榮;上野 勝司;阿部 隆之;中江 秀雄
• 通讯作者: 中江 秀雄

鋳造技術は何処まで進んだか?-その歴史的経緯と最新の製品・技術-

铸造技术进步到什么程度了？ - 其历史背景和最新产品技术 -

• 发表时间: 2004
• 期刊: 素形材
• 作者: 中江 秀雄

SiC粒子分散鋳鉄複合材料の自発的溶浸速度

SiC颗粒分散铸铁复合材料的自渗率

• 发表时间: 2004
• 期刊: 鋳造工学 76
• 作者: 顧 紅星;中江 秀雄
• 通讯作者: 中江 秀雄

The SEMI-FULL Mold Process Steel Casings.

半全模工艺钢外壳。

• 发表时间: 2004
• 期刊: The 66th World Foundry Congress
• 作者: Yoda Fukuda;Kenichi Hayashi;Taiji Fukuo;Toshitake Kanno;Hideo Nakae
• 通讯作者: Hideo Nakae

Inter facial energy and structure in Al-Si alloys.

Al-Si 合金中的界面能和结构。

• 发表时间: 2003
• 期刊: Series in Materials Science and Engineering
• 作者: Hideo Nakae;Hideki Yamaura;Yuuta Sugiyama;Michiya Takagi;Kazuhiro Mae;Hideo Nakae
• 通讯作者: Hideo Nakae