Solidification

Frontmatter

Introduction

Abstract

Over the past two decades I have adopted the method of in-situ observations of the solidification phenomenon in metals in order to continue research into the questions of how molten metal solidifies within the mould and how to control the solidification structure of cast metals.

Atsumi Ohno

1. The Formation of Cast Structures

Abstract

The ingot in Fig. 1.1(a) is a 99.8% Al ingot made by pouring molten Al into the opening of a box-type metallic mould as shown in Fig. 1.2 and solidifying it. The depression in the head was formed by shrinkage when the ingot solidified, and this is referred to as a shrinkage pipe.

Atsumi Ohno

2. Controlling the Macro Structure of Cast Metals

Abstract

So far I have discussed how equiaxed crystals are formed. I have asserted that “The principal mechanism of the formation of equiaxed crystals is the separation of crystals from the mould wall in the initial stage of solidification prior to the formation of a stable solid shell.”

Atsumi Ohno

3. Application of the Separation Theory

Abstract

So far I have discussed my motives in beginning research into the solidification of metals, my advocacy of the crystal separation theory, and control of cast structures based on the separation theory. In brief, I have discussed the exceedingly simple principle that in order to obtain equiaxed crystals, one should ascertain where they form and then cause many crystals to form there and separate and precipitate. If one wants columnar crystals, one should ensure that the crystals do not separate from where they have formed.

Atsumi Ohno

Conclusion

Abstract

In bringing this discussion to a conclusion, I would like to mention the professors who have had a major influence on my research and several matters that I have kept in mind while carrying out my research.

Atsumi Ohno

Backmatter