In situ age hardening phenomenon observed in as-sprayed Al-Sc binary alloys is reported. This, along with substantial grain refinement in the as-sprayed alloys exhibited hardness in the range of 605 MPa (Al-0.3 wt% Sc) to 923 MPa (Al-0.8 wt% Sc) that are comparable to the optimum hardness values typically obtained by age hardening in similar as-cast alloys. Transmission electron microscopy of the spray deposits revealed densely spaced Al3Sc precipitates of about 10 nm suggesting in-situ age hardening of these alloys during spray forming. This behavior is attributed to the inherent heating cycle associated with the spray forming process and the rapid kinetics of Al3Sc precipitation. © 2017 Elsevier B.V.

Ravi Kumar

Department of Metallurgical and Materials Engineering

Raghukiran Nadimpalli

Sujith R

Harshal Agrawal

Rajashekhara Shabadi

Aluminum

Aluminum alloys

Binary alloys

Bins

Deposits

Grain refinement

Grain size and shape

Hardening

Hardness

High resolution transmission electron microscopy

Mechanical properties

Metallurgy

microstructure

Precipitation (chemical)

Rapid Solidification

SCANDIUM ALLOYS

SPRAY STEELMAKING

Transmission electron microscopy

AL3SC PRECIPITATES

ALLOY DEPOSITS

HARDNESS VALUES

HEATING CYCLES

METALS AND ALLOYS

SPRAY DEPOSITS

spray forming

SPRAY FORMING PROCESS

Age hardening

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Journal of Alloys and Compounds

Journal of Phase Equilibria and Diffusion

On the Solubility of Group IV Elements (Ti, Zr, Hf) in Liquid Aluminum Below 800°C

Materials Characterization

Precipitation in cold-rolled Al–Sc–Zr and Al–Mn–Sc–Zr alloys prepared by powder metallurgy

Materials & Design

The effect of Sc additions on the microstructure and age hardening behaviour of as cast Al–Sc alloys

Materials Science and Engineering: A

On the addition of precipitation- and work-hardening in an Al–Sc alloy

<jats:p>The indentation load-displacement behavior of six materials tested with a Berkovich indenter has been carefully documented to establish an improved method for determining hardness and elastic modulus from indentation load-displacement data. The materials included fused silica, soda–lime glass, and single crystals of aluminum, tungsten, quartz, and sapphire. It is shown that the load–displacement curves during unloading in these materials are not linear, even in the initial stages, thereby suggesting that the flat punch approximation used so often in the analysis of unloading data is not entirely adequate. An analysis technique is presented that accounts for the curvature in the unloading data and provides a physically justifiable procedure for determining the depth which should be used in conjunction with the indenter shape function to establish the contact area at peak load. The hardnesses and elastic moduli of the six materials are computed using the analysis procedure and compared with values determined by independent means to assess the accuracy of the method. The results show that with good technique, moduli can be measured to within 5%.</jats:p>

Journal of Materials Research

An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments

In situ age hardening and grain refinement in as-sprayed Al-Sc binary alloy deposits

Journal	Data powered by TypesetJournal of Alloys and Compounds
Publisher	Data powered by TypesetElsevier Ltd
ISSN	09258388
Open Access	No