Journal article
Micro semi-solid manufacturing - A new technological approach towards miniaturisation
Publication Details
Authors: | Steinhoff, K.; Weidig, U.; Weikert, J. |
Publication year: | 2004 |
Journal: | Steel Research |
Pages range : | 611-619 |
Volume number: | 75 |
Issue number: | 8-9 |
Start page: | 611 |
End page: | 619 |
ISSN: | 0177-4832 |
DOI-Link der Erstveröffentlichung: |
Abstract
One of the most important prerequisites to meet the increasing demand for efficient technologies for micro-part production is constituted by the ability to overcome existing process limitations by new innovative technological approaches. By the introduction of a new process variant based on a hybrid material condition between solid and liquid state, such an approach is presented. This micro semi-solid manufacturing technology, so-called Micro-Thixoforming, was initiated, on the one hand, by being aware of the technological limits of existing microforming and micro-casting processes and, on the other hand, by a comprehensive understanding of the special rheological mechanisms of metallic materials in semi-solid state finally establishing the desired potential to follow the trend towards miniaturisation with drastically reduced process restrictions. However, this promising potential can only be successfully exploited when the initial idea, which is based on phenomenological considerations, can be transferred to a process technology with sufficient practical relevance. Therefore, the presented new integrated process concept for Micro-Thixoforming is particularly characterised by the application of unconventional solutions for the main process steps: raw material conditioning, thermal pre-processing, semi-solid forming and thermal post-processing. To give an indication of the innovative character of the chosen practical solutions liquid metal jet technology, LASER-induced plasma shockwaves and high pressure water jet should be mentioned. However, what is even more important in this context is the ability not only to realise a process concept but, beyond that, to recognise the further potential regarding new strategies for material design arising from the availability of this process. Such a strategy e.g. consists of utilising the well-known segregation effect, which notably often is negatively associated with semi-solid forming. However, for the envisaged technological approach, controlled segregation aims at a defined adjustment of functionally graded properties for the produced micro part.
One of the most important prerequisites to meet the increasing demand for efficient technologies for micro-part production is constituted by the ability to overcome existing process limitations by new innovative technological approaches. By the introduction of a new process variant based on a hybrid material condition between solid and liquid state, such an approach is presented. This micro semi-solid manufacturing technology, so-called Micro-Thixoforming, was initiated, on the one hand, by being aware of the technological limits of existing microforming and micro-casting processes and, on the other hand, by a comprehensive understanding of the special rheological mechanisms of metallic materials in semi-solid state finally establishing the desired potential to follow the trend towards miniaturisation with drastically reduced process restrictions. However, this promising potential can only be successfully exploited when the initial idea, which is based on phenomenological considerations, can be transferred to a process technology with sufficient practical relevance. Therefore, the presented new integrated process concept for Micro-Thixoforming is particularly characterised by the application of unconventional solutions for the main process steps: raw material conditioning, thermal pre-processing, semi-solid forming and thermal post-processing. To give an indication of the innovative character of the chosen practical solutions liquid metal jet technology, LASER-induced plasma shockwaves and high pressure water jet should be mentioned. However, what is even more important in this context is the ability not only to realise a process concept but, beyond that, to recognise the further potential regarding new strategies for material design arising from the availability of this process. Such a strategy e.g. consists of utilising the well-known segregation effect, which notably often is negatively associated with semi-solid forming. However, for the envisaged technological approach, controlled segregation aims at a defined adjustment of functionally graded properties for the produced micro part.
Keywords
controlled segregation, functionally graded properties, micro-casting, micro-forming, micro-thixoforming, size effect
