title: The Formulation of Titanium - based Metal Feedstocks and the Fabrication of Parts using the Powder Injection Moulding Process

authors: Ewart, Paul Douglas

subjects: Binder

abstract: Development of a profitable titanium industry for New Zealand will not come about without innovative technologies. Plastic injection moulding has long held a place in NZ manufacturing to produce large quantities of complex parts and holds the key to such innovation.
Titanium metal parts were fabricated by injection moulding titanium based metal powder feedstock followed by a debinding process and subsequent sintering. The fabrication process in its entirety was investigated in four distinct steps. Feedstock formulation involved combining the metal powders with various carrier components. Injection moulding enabled the shaping of the feedstock into geometries approximating the final part. Debinding being the process whereby the carrier/binder system is removed from the part to create a powder compact retaining the required geometry. Sintering being the final step where the metal powders are consolidated into a fully dense metal part of net shape.
The feedstock binder consisted of water soluble polyethylene glycol that reduced feedstock viscosity, improved particle wetting, aided greenpart shape retention and eliminated toxic solvents in debinding. Carnauba wax and bees wax aided dispersion, lubricated particles, were safe to handle and better for the environment (than petroleum waxes). Their low melt temperatures aided removal during thermal debinding and supported residue elimination.
By optimising the ratio of water soluble, wax and polyolefin binder components (3: 2: 1 respectively) for melt flow and pellet formation, greenparts defect free with uniform particle distribution were made. The optimal binder system proved suitable for titanium alloy and irregular shape pure titanium powders (hydride-de-hydride). Increasing powder loading (wP = (0.60 to 0.65)) had no appreciable effect on viscosity while enabling feedstock with good uniformity and pellet formation. Dimensional change was not affected by uniformity of the feedstock however molecular weight, volume and dispersion of binder components affected interparticular distances. Low processing temperatures reduced disruption to part geometry, benefitted particle bonding and helped retain handling strength.
The use of low temperatures for thermal debinding (t = 250 °C) enabled removal of the binder below the temperatures that facilitate interstitial diffusion and oxide/carbide formation, although part thickness, mass and overall volume effected the processing time. A strong correlation was seen between handling strength of the greenparts and defects, such as non-uniform density distribution and cracking after sintering.
Sintering was essential to produce the final part and showed that a binder free brownpart was not the only criteria for eliminating impurities. The furnace atmosphere must remain free from contamination to eliminate transfer back to the parts. This was addressed using an argon sweep gas, however, the design and efficacy of the system was considered inadequate. Decomposition products need to be removed quickly from the furnace as they evolve before impurities from the sweep gas diffuse back into the parts during the extended duration at sinter temperatures (t = 1300 °C).
The combination of an optimised titanium feedstock and the use of a low temperature thermal debinding technique produced a consolidated MIM part of relatively large dimensions. The parts were seen to have uniform microstructure throughout the cross-section with density comparable to that of MIM standards. In difference to the literature, a high powder loading (φp = 0.65) of HDH powders was used and shown to be readily mouldable. The higher powder loading also eliminate separation defects and shape distortions evident using lower amounts of powder.

text: The Formulation of Titanium - based Metal Feedstocks and the Fabrication of Parts using the Powder Injection Moulding Process Development of a profitable titanium industry for New Zealand will not come about without innovative technologies. Plastic injection moulding has long held a place in NZ manufacturing to produce large quantities of complex parts and holds the key to such innovation.
Titanium metal parts were fabricated by injection moulding titanium based metal powder feedstock followed by a debinding process and subsequent sintering. The fabrication process in its entirety was investigated in four distinct steps. Feedstock formulation involved combining the metal powders with various carrier components. Injection moulding enabled the shaping of the feedstock into geometries approximating the final part. Debinding being the process whereby the carrier/binder system is removed from the part to create a powder compact retaining the required geometry. Sintering being the final step where the metal powders are consolidated into a fully dense metal part of net shape.
The feedstock binder consisted of water soluble polyethylene glycol that reduced feedstock viscosity, improved particle wetting, aided greenpart shape retention and eliminated toxic solvents in debinding. Carnauba wax and bees wax aided dispersion, lubricated particles, were safe to handle and better for the environment (than petroleum waxes). Their low melt temperatures aided removal during thermal debinding and supported residue elimination.
By optimising the ratio of water soluble, wax and polyolefin binder components (3: 2: 1 respectively) for melt flow and pellet formation, greenparts defect free with uniform particle distribution were made. The optimal binder system proved suitable for titanium alloy and irregular shape pure titanium powders (hydride-de-hydride). Increasing powder loading (wP = (0.60 to 0.65)) had no appreciable effect on viscosity while enabling feedstock with good uniformity and pellet formation. Dimensional change was not affected by uniformity of the feedstock however molecular weight, volume and dispersion of binder components affected interparticular distances. Low processing temperatures reduced disruption to part geometry, benefitted particle bonding and helped retain handling strength.
The use of low temperatures for thermal debinding (t = 250 °C) enabled removal of the binder below the temperatures that facilitate interstitial diffusion and oxide/carbide formation, although part thickness, mass and overall volume effected the processing time. A strong correlation was seen between handling strength of the greenparts and defects, such as non-uniform density distribution and cracking after sintering.
Sintering was essential to produce the final part and showed that a binder free brownpart was not the only criteria for eliminating impurities. The furnace atmosphere must remain free from contamination to eliminate transfer back to the parts. This was addressed using an argon sweep gas, however, the design and efficacy of the system was considered inadequate. Decomposition products need to be removed quickly from the furnace as they evolve before impurities from the sweep gas diffuse back into the parts during the extended duration at sinter temperatures (t = 1300 °C).
The combination of an optimised titanium feedstock and the use of a low temperature thermal debinding technique produced a consolidated MIM part of relatively large dimensions. The parts were seen to have uniform microstructure throughout the cross-section with density comparable to that of MIM standards. In difference to the literature, a high powder loading (φp = 0.65) of HDH powders was used and shown to be readily mouldable. The higher powder loading also eliminate separation defects and shape distortions evident using lower amounts of powder.

year: 2015

title: A study of the impact of foreign direct investment on firms in the Chinese wine industry

authors: Yin, Haolin

subjects: FDI

abstract: The purpose of this thesis is to examine the process by which emerging market firms leverage foreign resources and capabilities through linkages with foreign affiliates in the home country. This is achieved through a thorough examination of the inter-firm transfer of firm Ownership-specific advantages, resources and capabilities from locally-based foreign affiliates to local Chinese firms via joint ventures and non-equity-based collaborative partnerships.
The theoretical foundation of this study draws on the Linkage, Leverage and Learning (LLL) framework (Mathews, 2006a; 2017) within the broader contextual frameworks of the Investment Development Path (IDP) framework (Dunning & Narula, 1996) and the Ownership, Location and Internalisation (OLI) paradigm (Dunning, 2000; 2001). The particular focus of the study is on the Linkage and Leverage constructs.
A case study method, focused on the Chinese wine industry and its participants, is employed. Qualitative data was collected through 48 in-depth semi-structured interviews with firms (including wine producers, suppliers and distributors), wine institutes and wine bureaux.
This thesis finds that the leverage process encompasses three phases:
a) Application, or directly utilising foreign resources and capabilities without change;
b) Adaptation which involves incrementally changing foreign resources and capabilities and/or adjusting the existing resources and capabilities of local Chinese firms to better utilise foreign resources and capabilities; and
c) Amelioration, or remodelling original foreign resources and capabilities by fundamentally improving and innovating them to better fit the needs of local Chinese firms.
The leverage process shows that local Chinese firms not only learn from foreign affiliates, but also develop foreign resources and capabilities to upgrade their competences. Foreign multinationals contribute to the upgrading of local firms in the Chinese wine industry by introducing technology, techniques and experience in winegrowing and winemaking; expertise in corporate governance and vineyard management; and well-developed philosophies in the winery business. Further, the findings suggest that inward FDI (IFDI) has played a catalyst role in the development of the Chinese wine industry by a) expanding industrial scale, b) introducing winery business philosophies, c) closing the technology gap between the industry and its international counterparts, d) creating a climate for Sino-foreign communication regarding wine techniques, e) engaging in wine education, f) promoting local wine regions, and g) boosting industrial confidence.
The theoretical contributions of this thesis include the exploration of how the LLL framework can be employed in a home-country context; a richer understanding of “Leverage” within the LLL framework; and the development of a process model which illustrates IFDI’s impact on the upgrading of emerging market firms and their industry within the home country.
Although this research is limited contextually to the wine industry in China, it has implications for other emerging economies that have unique, competitive and irreplaceable Location-specific advantages attractive to IFDI. Public policies that seek to achieve industrial development in such economies can draw on the catalyst role of IFDI. Emerging market firms to gain greater access to foreign resources and capabilities by adopting the linkage-leverage-learning concept as a strategy in their home countries.

text: A study of the impact of foreign direct investment on firms in the Chinese wine industry The purpose of this thesis is to examine the process by which emerging market firms leverage foreign resources and capabilities through linkages with foreign affiliates in the home country. This is achieved through a thorough examination of the inter-firm transfer of firm Ownership-specific advantages, resources and capabilities from locally-based foreign affiliates to local Chinese firms via joint ventures and non-equity-based collaborative partnerships.
The theoretical foundation of this study draws on the Linkage, Leverage and Learning (LLL) framework (Mathews, 2006a; 2017) within the broader contextual frameworks of the Investment Development Path (IDP) framework (Dunning & Narula, 1996) and the Ownership, Location and Internalisation (OLI) paradigm (Dunning, 2000; 2001). The particular focus of the study is on the Linkage and Leverage constructs.
A case study method, focused on the Chinese wine industry and its participants, is employed. Qualitative data was collected through 48 in-depth semi-structured interviews with firms (including wine producers, suppliers and distributors), wine institutes and wine bureaux.
This thesis finds that the leverage process encompasses three phases:
a) Application, or directly utilising foreign resources and capabilities without change;
b) Adaptation which involves incrementally changing foreign resources and capabilities and/or adjusting the existing resources and capabilities of local Chinese firms to better utilise foreign resources and capabilities; and
c) Amelioration, or remodelling original foreign resources and capabilities by fundamentally improving and innovating them to better fit the needs of local Chinese firms.
The leverage process shows that local Chinese firms not only learn from foreign affiliates, but also develop foreign resources and capabilities to upgrade their competences. Foreign multinationals contribute to the upgrading of local firms in the Chinese wine industry by introducing technology, techniques and experience in winegrowing and winemaking; expertise in corporate governance and vineyard management; and well-developed philosophies in the winery business. Further, the findings suggest that inward FDI (IFDI) has played a catalyst role in the development of the Chinese wine industry by a) expanding industrial scale, b) introducing winery business philosophies, c) closing the technology gap between the industry and its international counterparts, d) creating a climate for Sino-foreign communication regarding wine techniques, e) engaging in wine education, f) promoting local wine regions, and g) boosting industrial confidence.
The theoretical contributions of this thesis include the exploration of how the LLL framework can be employed in a home-country context; a richer understanding of “Leverage” within the LLL framework; and the development of a process model which illustrates IFDI’s impact on the upgrading of emerging market firms and their industry within the home country.
Although this research is limited contextually to the wine industry in China, it has implications for other emerging economies that have unique, competitive and irreplaceable Location-specific advantages attractive to IFDI. Public policies that seek to achieve industrial development in such economies can draw on the catalyst role of IFDI. Emerging market firms to gain greater access to foreign resources and capabilities by adopting the linkage-leverage-learning concept as a strategy in their home countries.

year: 2021

title: Decolonisation as a social change framework and its impact on the development of Indigenous-based curricula for Helping Professionals in mainstream Tertiary Education Organisations

authors: Moeke-Pickering, Taima Materangatira

subjects: Indigenous Education

abstract: This research examined the social and political approaches that Indigenous peoples undertook to situate Indigenous-based education programmes in mainstream post-secondary/tertiary education organisations. Indigenous-based helping programmes assist to progress Indigenous aspirations for self-determination and are sites that center Indigenous worldviews. A decolonisation analysis framework that is embedded in the curriculum deepens students’ understanding about the impacts of imperialism, colonisation and post colonial issues. This thesis involved researching two Indigenous-based programmes that are based within mainstream tertiary institutes. The first is the Te Whiuwhiu o te Hau Maori Counselling degree programme which is based at the Waikato Institute of Technology (WINTEC) in Hamilton, Aotearoa, New Zealand. The other is the Native Human Services Social Work degree programme which is based at Laurentian University in Sudbury, Ontario, Canada. I start this thesis with “opening the circle” and situating the context for my research. Next is the literature review chapter. This chapter provides a review of decolonisation-colonisation, decolonisation frameworks within Indigenous education, self-determination and Indigenous peoples, and Maori and Native self-determination strategies relevant to health and education. I used a case study method combined with an Indigenous methodology to guide the research. This involved gathering key pieces of information as well as interviewing participants (graduates, tutors/faculty/developers) from each programme. In chapter four is the Te Whiuwhiu o te Hau case study and in chapter five is found the Native Human Services case study. Each case study covers pre-colonial and colonisation contexts and examines assimilative legislation on Indigenous education and health. The backgrounds of social work and counselling, Native social work and Maori counselling are also presented. In the case studies is the background and rationale for the development of each programme, as well as pertinent information on the course content. Chapter six presents on the findings and conclusion and chapter seven “closes the circle”. The main findings highlighted that Indigenous curricula and pedagogies embrace Indigenous theories and discourse relevant to the helping practice fields. Secondly, each programme fosters students to make positive changes for themselves, for their communities, and for their professions. Another finding is that faculty/tutors promote an inclusive Indigenous pedagogy in the classroom that incorporates cultural ceremonies, encourage personal introspection, builds cultural and professional skills, and teaches critical education. Both programmes reflected a pedagogy that taught students to counter negative narratives while instilling a critical analysis of decolonisation and colonisation. I propose that a decolonisation analysis is both a reflective and healing tool, in that students are provided with the hard evidence about their histories and what happened to their communities. I contend that Indigenous-based programmes contribute to the continuity of Indigenous culture and wellbeing of their communities and, that they play a vital role in advancing Indigenous education priorities.

text: Decolonisation as a social change framework and its impact on the development of Indigenous-based curricula for Helping Professionals in mainstream Tertiary Education Organisations This research examined the social and political approaches that Indigenous peoples undertook to situate Indigenous-based education programmes in mainstream post-secondary/tertiary education organisations. Indigenous-based helping programmes assist to progress Indigenous aspirations for self-determination and are sites that center Indigenous worldviews. A decolonisation analysis framework that is embedded in the curriculum deepens students’ understanding about the impacts of imperialism, colonisation and post colonial issues. This thesis involved researching two Indigenous-based programmes that are based within mainstream tertiary institutes. The first is the Te Whiuwhiu o te Hau Maori Counselling degree programme which is based at the Waikato Institute of Technology (WINTEC) in Hamilton, Aotearoa, New Zealand. The other is the Native Human Services Social Work degree programme which is based at Laurentian University in Sudbury, Ontario, Canada. I start this thesis with “opening the circle” and situating the context for my research. Next is the literature review chapter. This chapter provides a review of decolonisation-colonisation, decolonisation frameworks within Indigenous education, self-determination and Indigenous peoples, and Maori and Native self-determination strategies relevant to health and education. I used a case study method combined with an Indigenous methodology to guide the research. This involved gathering key pieces of information as well as interviewing participants (graduates, tutors/faculty/developers) from each programme. In chapter four is the Te Whiuwhiu o te Hau case study and in chapter five is found the Native Human Services case study. Each case study covers pre-colonial and colonisation contexts and examines assimilative legislation on Indigenous education and health. The backgrounds of social work and counselling, Native social work and Maori counselling are also presented. In the case studies is the background and rationale for the development of each programme, as well as pertinent information on the course content. Chapter six presents on the findings and conclusion and chapter seven “closes the circle”. The main findings highlighted that Indigenous curricula and pedagogies embrace Indigenous theories and discourse relevant to the helping practice fields. Secondly, each programme fosters students to make positive changes for themselves, for their communities, and for their professions. Another finding is that faculty/tutors promote an inclusive Indigenous pedagogy in the classroom that incorporates cultural ceremonies, encourage personal introspection, builds cultural and professional skills, and teaches critical education. Both programmes reflected a pedagogy that taught students to counter negative narratives while instilling a critical analysis of decolonisation and colonisation. I propose that a decolonisation analysis is both a reflective and healing tool, in that students are provided with the hard evidence about their histories and what happened to their communities. I contend that Indigenous-based programmes contribute to the continuity of Indigenous culture and wellbeing of their communities and, that they play a vital role in advancing Indigenous education priorities.

year: 2010