title: Effect of hot isostatic pressing on mechanical properties of Fe₄₁Cr₁₅Mo₁₄C₁₅B₆Y₂Co₇ BMG

authors: Chen, Qingjun

subjects: Bulk metallic glass

abstract: Fe-based bulk amorphous rods of 3 mm in diameter and a composition of Fe₄₁Cr₁₅Mo₁₄C₁₅B₆Y₂Co₇ were produced by copper mold casting. The as-cast amorphous rods contain a small (2%) fraction of pores. To close the pores, samples cut from the amorphous rods were hot isostatically pressed (hipped) at 863 K, which is in the supercooled liquid temperature range between the glass transition temperature and the crystallization temperature of the amorphous phase, and under a pressure of 200 Mpa. Microstructure examination of the hipped samples shows that hipping results in an increase of the density of the samples from 7.9 g/cm³ to 8.0 g/cm³, and a decrease of the porosity level from 2% to 1%, and that a very small fraction of unknown crystalline phase form. As a result of these microstructure change caused by hipping, the average room temperature compressive fracture strength of the bulk metallic glass (BMG) decrease from 3500 Mpa to 3000 MPa, while the strain to fracture changes little from 1.5% to 1.4%. The mechanisms of the effect of hipping on microstructure and mechanical properties of the Fe-based BMG are discussed.

text: Effect of hot isostatic pressing on mechanical properties of Fe₄₁Cr₁₅Mo₁₄C₁₅B₆Y₂Co₇ BMG Fe-based bulk amorphous rods of 3 mm in diameter and a composition of Fe₄₁Cr₁₅Mo₁₄C₁₅B₆Y₂Co₇ were produced by copper mold casting. The as-cast amorphous rods contain a small (2%) fraction of pores. To close the pores, samples cut from the amorphous rods were hot isostatically pressed (hipped) at 863 K, which is in the supercooled liquid temperature range between the glass transition temperature and the crystallization temperature of the amorphous phase, and under a pressure of 200 Mpa. Microstructure examination of the hipped samples shows that hipping results in an increase of the density of the samples from 7.9 g/cm³ to 8.0 g/cm³, and a decrease of the porosity level from 2% to 1%, and that a very small fraction of unknown crystalline phase form. As a result of these microstructure change caused by hipping, the average room temperature compressive fracture strength of the bulk metallic glass (BMG) decrease from 3500 Mpa to 3000 MPa, while the strain to fracture changes little from 1.5% to 1.4%. The mechanisms of the effect of hipping on microstructure and mechanical properties of the Fe-based BMG are discussed.

year: 2006

title: William Buchanan Maxwell: a veteran who became ‘Te Aroha’s pet adornment’

authors: Hart, Philip

abstract: Famous in Te Aroha as a veteran soldier, Maxwell had fought in the Crimea, China, and India before fighting against Maori in New Zealand. Proud of his four wounds, he would lead a detachment of volunteers marching off to war in 1915. In his personal life, despite his involvement in the New Zealand land wars he would marry a Maori. After the fighting ceased, he had a variety of low-skilled jobs in Rotorua, Tauranga, and Ohinemuri before settling in Te Aroha, where he was a fireman. At Te Aroha he did a little prospecting, but did not really deserve the title ‘miner’. His jovial personality made him one of Te Aroha’s most popular residents.

text: William Buchanan Maxwell: a veteran who became ‘Te Aroha’s pet adornment’ Famous in Te Aroha as a veteran soldier, Maxwell had fought in the Crimea, China, and India before fighting against Maori in New Zealand. Proud of his four wounds, he would lead a detachment of volunteers marching off to war in 1915. In his personal life, despite his involvement in the New Zealand land wars he would marry a Maori. After the fighting ceased, he had a variety of low-skilled jobs in Rotorua, Tauranga, and Ohinemuri before settling in Te Aroha, where he was a fireman. At Te Aroha he did a little prospecting, but did not really deserve the title ‘miner’. His jovial personality made him one of Te Aroha’s most popular residents.

year: 2016

title: From the rākau to the ngākau

authors: Derby, Melissa

subjects: research

abstract: The Ministry of Business, Innovation and Employment (MBIE) in Aotearoa New Zealand has funded 11 National Science Challenges (NSC), which aim to tackle a series of big questions affecting wellbeing in society. One Challenge, A Better Start: E Tipu E Rea, is investigating four key focus areas that children encounter in their early development and is seeking to identify the factors that contribute to forming a solid foundation for fostering wellbeing and lifelong success. Central to the principles of this Challenge is the Treaty of Waitangi in that the Treaty provides a framework to guide whānau engagement, policy change, and praxis. This article describes how a ‘ngākau’ rather than a ‘rākau’ approach to shaping research inquiry within this Challenge facilitates more authentic and mana-enhancing whānau engagement in research interactions (Macfarlane, 2019). The development of a whānau questionnaire is drawn on to illustrate the ngākau approach in practice.

text: From the rākau to the ngākau The Ministry of Business, Innovation and Employment (MBIE) in Aotearoa New Zealand has funded 11 National Science Challenges (NSC), which aim to tackle a series of big questions affecting wellbeing in society. One Challenge, A Better Start: E Tipu E Rea, is investigating four key focus areas that children encounter in their early development and is seeking to identify the factors that contribute to forming a solid foundation for fostering wellbeing and lifelong success. Central to the principles of this Challenge is the Treaty of Waitangi in that the Treaty provides a framework to guide whānau engagement, policy change, and praxis. This article describes how a ‘ngākau’ rather than a ‘rākau’ approach to shaping research inquiry within this Challenge facilitates more authentic and mana-enhancing whānau engagement in research interactions (Macfarlane, 2019). The development of a whānau questionnaire is drawn on to illustrate the ngākau approach in practice.

year: 2021