title: The effect of heat treatments on microstructure and mechanical properties of as-extruded Ti-6Al-4V alloy rod from blended elemental powders

authors: Romero Villarreal, Carlos

abstract: In this study, Ti-6Al-4V bars were first prepared by extrusion of powder compacts from blended powder mixtures in the beta phase region, then the as-extruded bars were heat-treated following four different conditions: beta quenching and aging (βQA), broken up structure (BUS) treatment, solution treatment and aging (STA) and recrystallization annealing (RA). The effect of the heat treatments on microstructure and mechanical properties was studied using optical microscopy, scanning electron microscopy, and mechanical test to determine which heat treatment condition has the greatest impact on the mechanical properties of the as-extruded Ti-6Al-4V alloy. The results show that the as-extruded condition has the best balance of strength (1120 MPa of UTS) and ductility (11% of elongation to failure). βQA and STA lead to a slight increase in strength but ductility decreases considerably. After BUS and RA treatments, both strength and ductility are reduced. The relationship between processing, microstructure and properties was studied, and their implications towards fatigue behaviour and fracture toughness discussed.

text: The effect of heat treatments on microstructure and mechanical properties of as-extruded Ti-6Al-4V alloy rod from blended elemental powders In this study, Ti-6Al-4V bars were first prepared by extrusion of powder compacts from blended powder mixtures in the beta phase region, then the as-extruded bars were heat-treated following four different conditions: beta quenching and aging (βQA), broken up structure (BUS) treatment, solution treatment and aging (STA) and recrystallization annealing (RA). The effect of the heat treatments on microstructure and mechanical properties was studied using optical microscopy, scanning electron microscopy, and mechanical test to determine which heat treatment condition has the greatest impact on the mechanical properties of the as-extruded Ti-6Al-4V alloy. The results show that the as-extruded condition has the best balance of strength (1120 MPa of UTS) and ductility (11% of elongation to failure). βQA and STA lead to a slight increase in strength but ductility decreases considerably. After BUS and RA treatments, both strength and ductility are reduced. The relationship between processing, microstructure and properties was studied, and their implications towards fatigue behaviour and fracture toughness discussed.

year: 2018

title: Funkin' Cultural Boundaries: Popular Music and Socio-Spatial Change

authors: Timbs, Darnelle

subjects: Music

abstract: In recent decades retheorised perspectives have transformed geographical studies of music. Human geographers have examined issues of music, place and identity in a range of empirical settings, theoretical frameworks and policy contexts. As a cultural sphere in which identities are created and challenged, music is a medium through which boundaries are established and transgressed, and in which difference is marked out and challenged. For marginalised or oppressed groups music provides a medium through which to create spaces to represent themselves and their aspirations. With contemporary cultural and economic processes having eroded senses of spatial distance, spaces of identity express complex fusions between the global and the local. Music is no longer integrally tied to specific ethnic groups; music results from numerous stylistic practices and transnational human musical interactions.

The music of the hip hop group the Black Eyed Peas exemplifies the boundary-challenging aesthetic of hybrid music. Evidence collected through face-to-face interviews and participant observation highlights the ways in which the Black Eyed Peas employ their music to unsettle existing economic and social conditions. Discussion of how the Black Eyed Peas transgress economic barriers, challenge musical expectations, and expose the experiences of 'others' reveals the power relations that manifest in boundary creation and maintenance. Comments from members of the Black Eyed Peas and their associates expose the contradictions and compromises implicit in efforts to relocate social boundaries. Conflict between transgressive intentions is exhibited in the fundraising activities of the Peapod Foundation, a charitable organisation managed by the Black Eyed Peas.

text: Funkin' Cultural Boundaries: Popular Music and Socio-Spatial Change In recent decades retheorised perspectives have transformed geographical studies of music. Human geographers have examined issues of music, place and identity in a range of empirical settings, theoretical frameworks and policy contexts. As a cultural sphere in which identities are created and challenged, music is a medium through which boundaries are established and transgressed, and in which difference is marked out and challenged. For marginalised or oppressed groups music provides a medium through which to create spaces to represent themselves and their aspirations. With contemporary cultural and economic processes having eroded senses of spatial distance, spaces of identity express complex fusions between the global and the local. Music is no longer integrally tied to specific ethnic groups; music results from numerous stylistic practices and transnational human musical interactions.

The music of the hip hop group the Black Eyed Peas exemplifies the boundary-challenging aesthetic of hybrid music. Evidence collected through face-to-face interviews and participant observation highlights the ways in which the Black Eyed Peas employ their music to unsettle existing economic and social conditions. Discussion of how the Black Eyed Peas transgress economic barriers, challenge musical expectations, and expose the experiences of 'others' reveals the power relations that manifest in boundary creation and maintenance. Comments from members of the Black Eyed Peas and their associates expose the contradictions and compromises implicit in efforts to relocate social boundaries. Conflict between transgressive intentions is exhibited in the fundraising activities of the Peapod Foundation, a charitable organisation managed by the Black Eyed Peas.

year: 2007

title: Contextualising Māori writing: a study of prose fiction written in English by Witi Ihimaera, Patricia Grace, Keri Hulme and Alan Duff

authors: Calvert, Julia Helen

abstract: All prose fiction written in English by Māori is political on one level or another. The authors considered in this thesis, Witi Ihimaera, Patricia Grace, Keri Hulme and Alan Duff, choose to identify as Māori, but for each writer exactly what this entails implies something different. The diverse range of Māori characters represented in their work illustrates the heterogeneity of contemporary Māori identity. Whilst bearing in mind that there is no fixed Māori identity, this thesis proposes that all fiction written in English by Māori is motivated by a belief that Māori are a disadvantaged group within New Zealand society. 

Three of the four writers, Ihimaera, Grace and Hulme, write against a background of colonisation. Their fiction confronts grievances based on perceived injustices committed against Māori in the past by European colonists and is concerned with the restoration of Māori rights pertaining to land, language, identity and political voice. While all three engage with these issues in their fiction, this thesis specifically considers the way in which Ihimaera treats the theme of land, Grace focuses on issues of education and Hulme explores Māori mythology.

Alan Duff stands apart from the other three writers in his belief that colonisation is not to blame for contemporary Māori disadvantage. Rather, Duff considers the situation to be the result of inherent flaws within Māori society. Through his often didactic writing he proposes that improved Māori socioeconomic levels can only be achieved through a radical structural and economic re-evaluation of Māori culture.

This thesis contextualises the work of the four authors and explores the ways in which their fiction engages with historical and contemporary issues of “race relations” and cultural identity in New Zealand. A sociological approach has been applied to the texts. This approach derives from the Māori writers’ own insistent reading of contemporary Māori identity as the product of historical encounter between Māori and Pākehā. The authors work in a dialectical relationship to previous Pākehā representations of Māori in literature, are historically revisionist, and are frequently adversarial. 

Despite the differences in personal and political perspectives held by the authors, their fictions share a common goal in their search for Māori pathways to empowerment. This thesis argues that prose fiction written in English by Māori writers contributes to the political activism of the Māori people and helps to foster an environment in which new perspectives on Māori culture and bicultural relations can be articulated.

text: Contextualising Māori writing: a study of prose fiction written in English by Witi Ihimaera, Patricia Grace, Keri Hulme and Alan Duff All prose fiction written in English by Māori is political on one level or another. The authors considered in this thesis, Witi Ihimaera, Patricia Grace, Keri Hulme and Alan Duff, choose to identify as Māori, but for each writer exactly what this entails implies something different. The diverse range of Māori characters represented in their work illustrates the heterogeneity of contemporary Māori identity. Whilst bearing in mind that there is no fixed Māori identity, this thesis proposes that all fiction written in English by Māori is motivated by a belief that Māori are a disadvantaged group within New Zealand society. 

Three of the four writers, Ihimaera, Grace and Hulme, write against a background of colonisation. Their fiction confronts grievances based on perceived injustices committed against Māori in the past by European colonists and is concerned with the restoration of Māori rights pertaining to land, language, identity and political voice. While all three engage with these issues in their fiction, this thesis specifically considers the way in which Ihimaera treats the theme of land, Grace focuses on issues of education and Hulme explores Māori mythology.

Alan Duff stands apart from the other three writers in his belief that colonisation is not to blame for contemporary Māori disadvantage. Rather, Duff considers the situation to be the result of inherent flaws within Māori society. Through his often didactic writing he proposes that improved Māori socioeconomic levels can only be achieved through a radical structural and economic re-evaluation of Māori culture.

This thesis contextualises the work of the four authors and explores the ways in which their fiction engages with historical and contemporary issues of “race relations” and cultural identity in New Zealand. A sociological approach has been applied to the texts. This approach derives from the Māori writers’ own insistent reading of contemporary Māori identity as the product of historical encounter between Māori and Pākehā. The authors work in a dialectical relationship to previous Pākehā representations of Māori in literature, are historically revisionist, and are frequently adversarial. 

Despite the differences in personal and political perspectives held by the authors, their fictions share a common goal in their search for Māori pathways to empowerment. This thesis argues that prose fiction written in English by Māori writers contributes to the political activism of the Māori people and helps to foster an environment in which new perspectives on Māori culture and bicultural relations can be articulated.

year: 2002