title: Joint effect of β-eutectoid content and heat treatment on the properties of binary Ti-Cu and Ti-Mn alloys

authors: Bolzoni, Leandro

subjects: Titanium alloys

abstract: The use of cheap alloying elements and alternative manufacturing techniques are two strategies that can be used to reduce the high cost of Ti alloys. Furthermore, heat treatments are an easy and cost effective method to tailor the mechanical behaviour by means of the modification of the microstructure. For that, this work analysed the quenching and aging heat treatment of binary Ti-Cu and Ti-Mn alloys manufactured via powder metallurgy. It is found that the post-processing solution treatment does not significantly affect the physical properties and residual porosity remains unchanged within the microstructure; however, the heat treatment changes the microconstituents. Serrated martensitic transformed β is formed in quenched Ti-Cu alloys and it is converted into a coarse lamellar or a hypoeutectoid structure as the Cu content increases with the subsequent aging treatment. Aging of the Ti-Mn alloys slightly coarsen the microstructural features where martensite or equiaxed metastable β grains are obtained after quenching. Enhancing of the mechanical behaviour is generally achieved and the solution treatment switches from improving the ductility to increasing the strength and the hardness as the amount of the alloying element increases.

text: Joint effect of β-eutectoid content and heat treatment on the properties of binary Ti-Cu and Ti-Mn alloys The use of cheap alloying elements and alternative manufacturing techniques are two strategies that can be used to reduce the high cost of Ti alloys. Furthermore, heat treatments are an easy and cost effective method to tailor the mechanical behaviour by means of the modification of the microstructure. For that, this work analysed the quenching and aging heat treatment of binary Ti-Cu and Ti-Mn alloys manufactured via powder metallurgy. It is found that the post-processing solution treatment does not significantly affect the physical properties and residual porosity remains unchanged within the microstructure; however, the heat treatment changes the microconstituents. Serrated martensitic transformed β is formed in quenched Ti-Cu alloys and it is converted into a coarse lamellar or a hypoeutectoid structure as the Cu content increases with the subsequent aging treatment. Aging of the Ti-Mn alloys slightly coarsen the microstructural features where martensite or equiaxed metastable β grains are obtained after quenching. Enhancing of the mechanical behaviour is generally achieved and the solution treatment switches from improving the ductility to increasing the strength and the hardness as the amount of the alloying element increases.

year: 2024

title: Piloting a telemetric data tracking system to assess post-training real driving performance of young novice drivers

authors: Isler, Robert B.

subjects: driver training

abstract: Evaluating the effects of driver training interventions is a difficult research task. The ultimate goal of such interventions is to make the driver safer and therefore less likely to be involved in a road crash. A particular driver training intervention can only be considered to be effective if it can show a significant reduction in the number crashes for the driver, or a significant change in driver behaviour that clearly implies safer driving. Getting accurate and comprehensive crash records is difficult and to measure post training behavioural driving changes based on selfreports (e.g., log books) may not be accurate enough to be statistically meaningful.

text: Piloting a telemetric data tracking system to assess post-training real driving performance of young novice drivers Evaluating the effects of driver training interventions is a difficult research task. The ultimate goal of such interventions is to make the driver safer and therefore less likely to be involved in a road crash. A particular driver training intervention can only be considered to be effective if it can show a significant reduction in the number crashes for the driver, or a significant change in driver behaviour that clearly implies safer driving. Getting accurate and comprehensive crash records is difficult and to measure post training behavioural driving changes based on selfreports (e.g., log books) may not be accurate enough to be statistically meaningful.

year: 2008

title: Whānau mentoring, Māori youth and crime

authors: Joseph, Robert

abstract: This article will discuss how the whänau was the traditional institution for teaching and nurturing children through (among other things) effective mentoring, and how children were taught tikanga, or the ‘right way’ to think, speak, act and become. Traditional leadership development, whänau dysfunction and whänau renewal are also discussed, followed by my conclusions. This article will not be discussing the place of colonisation, high unemployment, lower education rates and other socio-economic disparities among Mäori that play a part in the causes and perpetuation of Mäori youth and crime. A discussion on the Treaty of Waitangi, indigenous rights, and Mäori development is also omitted although the importance of each of these areas is acknowledged. As the theme of this issue of Childrenz Issues is ‘seeking pathways beyond colonisation’, the focus of this article is on Mäori dealing appropriately with the problems of Mäori youth and crime through effective mentoring within the institution of the whänau.

text: Whānau mentoring, Māori youth and crime This article will discuss how the whänau was the traditional institution for teaching and nurturing children through (among other things) effective mentoring, and how children were taught tikanga, or the ‘right way’ to think, speak, act and become. Traditional leadership development, whänau dysfunction and whänau renewal are also discussed, followed by my conclusions. This article will not be discussing the place of colonisation, high unemployment, lower education rates and other socio-economic disparities among Mäori that play a part in the causes and perpetuation of Mäori youth and crime. A discussion on the Treaty of Waitangi, indigenous rights, and Mäori development is also omitted although the importance of each of these areas is acknowledged. As the theme of this issue of Childrenz Issues is ‘seeking pathways beyond colonisation’, the focus of this article is on Mäori dealing appropriately with the problems of Mäori youth and crime through effective mentoring within the institution of the whänau.

year: 2007-01