title: Preparation, microstructure and properties of Ti-6Al-4V rods by powder compact extrusion of powder mixture

authors: Yang, Fei

subjects: Extrusion

abstract: Ti-6Al-4V (wt%) alloy rods were prepared successfully using a low-cost method that combines mixing elemental and master alloy powders and powder compact extrusion. The microstructure and mechanical properties of the rods and the effects of extrusion temperature on them were investigated. The results showed that the microstructure and mechanical properties of the extruded rods were strongly affected by the extrusion temperature. With increasing extrusion temperature from 1200°C to 1300°C and keeping the powder compact holding time unchanged at 2 minutes, the fraction of undissolved V rich particles in the microstructure of the extruded rod decreased substantially to zero, the level of composition homogenization increased dramatically to the highest level, and the UTS and elongation of the extruded rods increased significantly from 886MPa and 1.2% to 1300MPa and 7.1%, respectively. The tensile properties of the Ti-6Al-4V alloy rods produced by powder compact extrusion of the powder mixture are comparable to those of Ti-6Al-4V alloy produced by ingot metallurgy and thermomechanical processing.

text: Preparation, microstructure and properties of Ti-6Al-4V rods by powder compact extrusion of powder mixture Ti-6Al-4V (wt%) alloy rods were prepared successfully using a low-cost method that combines mixing elemental and master alloy powders and powder compact extrusion. The microstructure and mechanical properties of the rods and the effects of extrusion temperature on them were investigated. The results showed that the microstructure and mechanical properties of the extruded rods were strongly affected by the extrusion temperature. With increasing extrusion temperature from 1200°C to 1300°C and keeping the powder compact holding time unchanged at 2 minutes, the fraction of undissolved V rich particles in the microstructure of the extruded rod decreased substantially to zero, the level of composition homogenization increased dramatically to the highest level, and the UTS and elongation of the extruded rods increased significantly from 886MPa and 1.2% to 1300MPa and 7.1%, respectively. The tensile properties of the Ti-6Al-4V alloy rods produced by powder compact extrusion of the powder mixture are comparable to those of Ti-6Al-4V alloy produced by ingot metallurgy and thermomechanical processing.

year: 2012

title: Evolving genres in online domains: the hybrid genre of the participatory news article

authors: Bruce, Ian

subjects: text

abstract: The genre modelling and research presented in this chapter originate from the sub-branch of Applied Linguistics concerned with theorising and designing courses for the teaching of academic literacy skills. Specifically, a model previously employed in the analysis of academic genres [13– 18] is used here as a basis for examining the particular web genre of an online news article followed by postings of reader comments – termed here a participatory news article. The chapter first provides an overview of approaches to the categorisation of texts in terms of genres, referring to a number of landmark studies and publications and considering some of the key difficulties in establishing systematic and comprehensive models that are able to account for all of the types of knowledge that writers and readers draw upon in order to identify and ratify a text as belonging to a particular genre category.

text: Evolving genres in online domains: the hybrid genre of the participatory news article The genre modelling and research presented in this chapter originate from the sub-branch of Applied Linguistics concerned with theorising and designing courses for the teaching of academic literacy skills. Specifically, a model previously employed in the analysis of academic genres [13– 18] is used here as a basis for examining the particular web genre of an online news article followed by postings of reader comments – termed here a participatory news article. The chapter first provides an overview of approaches to the categorisation of texts in terms of genres, referring to a number of landmark studies and publications and considering some of the key difficulties in establishing systematic and comprehensive models that are able to account for all of the types of knowledge that writers and readers draw upon in order to identify and ratify a text as belonging to a particular genre category.

year: 2011

title: Is the web being used to speak our language?

authors: Keegan, Te Taka Adrian Gregory

subjects: WWW

abstract: This paper presents results from extensive surveys of the usage of Maori language on the World Wide Web(www, Web) conducted in 1998 and 2002. Issues both supportive and detrimental relating to the use and publication of indigenous languages in the WWW will be highlighted. Specifically: how is the WWW being used to articulate the Maori language?

text: Is the web being used to speak our language? This paper presents results from extensive surveys of the usage of Maori language on the World Wide Web(www, Web) conducted in 1998 and 2002. Issues both supportive and detrimental relating to the use and publication of indigenous languages in the WWW will be highlighted. Specifically: how is the WWW being used to articulate the Maori language?

year: 2004