In-situ formed, ultrafine Al-Si composite materials: ductility
Journal Title: Journal of Achievements in Materials and Manufacturing Engineering - Year 2019, Vol 1, Issue 92
Abstract
Purpose: The work objective includes optimization of the casting production and heat treatment processes that will simultaneously maximize the combination of strength, hardness, and ductility for hypereutectic Al-Si compositions with Si volume fractions of as much as 25 vol.%. In addition, such an in-situ formed composite alloy will attain a unique combination of low production cost, high potential recycled content, and functional characteristics suitable for mission critical aerospace and vehicular applications. Design/methodology/approach: The unique High Pressure Die Casting Universal Metallurgical Simulator and Analyser (HPDC UMSA) was used for melting, cyclic melt treatment, and solidification of the hypereutectic Al-Si-X (A390). The produced as-cast structures contained colonies of nano-diameter Si whiskers and other morphologies, and absence of primary silicon particles. Heat treated structures rendered nano and ultrafine metal matrix composites. Findings: New developed as-cast Al-Si materials containing nano-diameter Si whiskers, without primary silicon particles required ultra short time heat treatment to result in nano and ultrafine metal matrix composite, rendering their hardness, strength and wear resistance, and the same time retaining toughness and ductility. Research limitations/implications: The cast samples were produced in laboratory conditions and potential tensile strength was estimated from empirical correlation with micro-hardness measurements. In the future, the comprehensive mechanical properties need to be tested. Practical implications: These ultrafine Si, Al-MMCs can be net-shape formed by modified HPDC technology or consolidated from spray-atomized alloy powder. Originality/value: Optimization of the entire production process for the hypereutectic Al-Si alloy compositions achieved a uniform distribution of ~ 25 vol.% of ultrafine Si particles in ductile FCC-Al matrix further reinforced by age hardening with nano-scale spinodal GP-zones. The associated mechanical property and ductility improvements will open a wide range of critical lightweighting components in transportation: aerospace, terrestrial vehicle and marine to the optimized hypereutectic Al-Si alloys. Presently, these components do not use the commercial HPDC A390 alloys due to their limited ductility and strength. Proposed new technology will allow conversion of various cast airspace alloys with ultrahigh mechanical properties to the automotive applications.<br/><br/>
Authors and Affiliations
P. Guba, A. Gesing, J. Sokolowski, S. Das, M. Kasprzak
Keywords
Related Articles
- EP ID EP640691
- DOI 10.5604/01.3001.0013.3182
- Views 83
- Downloads 0
Distribution of forces on supporting teeth in the midpalatal expander during “Hyrax” screw pre-load
Purpose: The aim of the study was to determine forces which are transferred to supporting teeth during the treatment with the midpalatal device with Hyrax screw and to evaluate orthodontic and orthopaedic effects based o...
Investigation of mechanical properties of MIG-brazed joints of DP600 steel plates using different working angle
Purpose: In this study, DP 600 (Dual Phase) steel plates having 1 mm thickness were joined by copper-based (CuAl8) wire in gas metal arc brazing technique. Specimens were prepared in joining forms as overlap joint. Desig...
Nanocomposite Ni/diamond layers produced by the electrocrystallization method
Purpose: The aim of this paper concerns the manufacturing of nanocomposite Ni/diamondsurface layers deposited on S235JR carbon steel using electrocrystallization method andexaminations of their structures and properties....
Determination of the optimal parameters of the structure of functional gradient materials using mathematical modelling approaches
Purpose: Functioning of mechanical friction systems largely depends on the characteristics of the structure of their surface layers. By controlling these parameters, it is possible to significantly adjus...
Situational model of technological operations for secondary metallurgy
Purpose: The aim of this study was development of a computer situational model of heat and power processes and transport operations for secondary steelmaking (SSM) to evaluate the effectiveness of the proposed SSM energy...