title: Advancement in the pressureless sintering of CP titanium using high-frequency induction heating

authors: Raynova, Stiliana (Stella) Rousseva

subjects: Science & Technology

abstract: High-frequency induction heating is applied as an alternative heating source for pressureless sintering of commercially pure Ti powders, aiming to intensify the sintering process. The effects of the process parameters on the properties of the sintered material are systematically studied. The initial powder compact density is the most influential parameter permitting sintered structures with highly porous to almost fully dense appearance. Short heating time combined with sintering to temperatures just above the β-transus resulted in a strong diffusion bonding between the Ti powder particles, and grain growth is observed at the former boundaries of the neighboring powder particles. The dimpled appearance of the fracture surface at those regions confirmed the strong metallic interparticle bonding. Tensile properties comparable to those of Ti-Grade 3 and Ti-Grade 4 are achieved, which also demonstrates the efficiency of the induction sintering process. A mechanism explaining the fast and efficient sintering is proposed. The process has the added advantage of minimizing the oxygen pickup.

text: Advancement in the pressureless sintering of CP titanium using high-frequency induction heating High-frequency induction heating is applied as an alternative heating source for pressureless sintering of commercially pure Ti powders, aiming to intensify the sintering process. The effects of the process parameters on the properties of the sintered material are systematically studied. The initial powder compact density is the most influential parameter permitting sintered structures with highly porous to almost fully dense appearance. Short heating time combined with sintering to temperatures just above the β-transus resulted in a strong diffusion bonding between the Ti powder particles, and grain growth is observed at the former boundaries of the neighboring powder particles. The dimpled appearance of the fracture surface at those regions confirmed the strong metallic interparticle bonding. Tensile properties comparable to those of Ti-Grade 3 and Ti-Grade 4 are achieved, which also demonstrates the efficiency of the induction sintering process. A mechanism explaining the fast and efficient sintering is proposed. The process has the added advantage of minimizing the oxygen pickup.

year: 2019

title: The Piako County tramway at Waiorongomai

authors: Hart, Philip

abstract: This tramway, the main engineering feature of the goldfield, as difficult and expensive both to construct and to maintain, but without it mining was impossible. Involving three inclines and three levels, with a short trestle joining it to the battery, it served most of the mines, most of which were above it and linked by chutes or short tramways. It was neither cheap nor easy to operate, partly because of the topography and the weather.
To construct it required much more financial assistance from the county council and the government than originally envisaged. Surveying the route took five months, and construction was prolonged as the cost escalated. Once in use it was found to need modifications and over the years many repairs were required. Miners claimed its charges were exorbitant, and because of the high cost of running it some wanted it leased, which did happen for a time. Whatever form of ownership and whoever was the tramway manager, it was never cheap to run and complaints about costs continued; and government financial assistance was obtained periodically, and reluctantly.
After the First World War, the county was convinced to retain the rails and even to make more repairs, but the latter ceased after 1924 and the line was abandoned and became unusable. Not even the minor revival of mining during the Depression convinced local or central government to repair it, and in the early 1940s many rails were stolen.
There were many accidents during its operation, but only one fatality.

text: The Piako County tramway at Waiorongomai This tramway, the main engineering feature of the goldfield, as difficult and expensive both to construct and to maintain, but without it mining was impossible. Involving three inclines and three levels, with a short trestle joining it to the battery, it served most of the mines, most of which were above it and linked by chutes or short tramways. It was neither cheap nor easy to operate, partly because of the topography and the weather.
To construct it required much more financial assistance from the county council and the government than originally envisaged. Surveying the route took five months, and construction was prolonged as the cost escalated. Once in use it was found to need modifications and over the years many repairs were required. Miners claimed its charges were exorbitant, and because of the high cost of running it some wanted it leased, which did happen for a time. Whatever form of ownership and whoever was the tramway manager, it was never cheap to run and complaints about costs continued; and government financial assistance was obtained periodically, and reluctantly.
After the First World War, the county was convinced to retain the rails and even to make more repairs, but the latter ceased after 1924 and the line was abandoned and became unusable. Not even the minor revival of mining during the Depression convinced local or central government to repair it, and in the early 1940s many rails were stolen.
There were many accidents during its operation, but only one fatality.

year: 2016

title: Kaumātua mana motuhake: Kaumātua managing life-transitions through tuakana-teina/peer-education

authors: Hokowhitu, Brendan

abstract: People face signifi cant transition points as they age, such as loss of independent living, loss of a spouse and changing health conditions. Successfully navigating these transitions depends on being able to manage emotional and socio-economic factors, as well as service systems, while often being reliant on family or whānau. Historically however, kaumātua have faced a dominant society that has failed to realise their full potential as they age. Yet, for Māori, kaumātua are “carriers of culture, anchors for families, models for lifestyle, bridges to the future, guardians of heritage and role models for younger generations.” Kaumātua mana motuhake is invested in upholding kaumātua tino rangatiratanga (independence and autonomy) via high-quality Māori research that will lead to better life outcomes for kaumātua and their whā nau.

text: Kaumātua mana motuhake: Kaumātua managing life-transitions through tuakana-teina/peer-education People face signifi cant transition points as they age, such as loss of independent living, loss of a spouse and changing health conditions. Successfully navigating these transitions depends on being able to manage emotional and socio-economic factors, as well as service systems, while often being reliant on family or whānau. Historically however, kaumātua have faced a dominant society that has failed to realise their full potential as they age. Yet, for Māori, kaumātua are “carriers of culture, anchors for families, models for lifestyle, bridges to the future, guardians of heritage and role models for younger generations.” Kaumātua mana motuhake is invested in upholding kaumātua tino rangatiratanga (independence and autonomy) via high-quality Māori research that will lead to better life outcomes for kaumātua and their whā nau.

year: 2017