Effect of the Temperature Gradient, Growth Rate, and the Interflake Spacing on the Microhardness in the Directionally Solidified Al-Si Eutectic Alloy

Sn – Cd eutectic melt was first obtained in a hot filling furnace and then directionally solidified upward with different growth rate ranges (8.1–165 μm/s) at a constant temperature gradient G (4.35 K/mm) in the Bridgman-type directional solidification furnace. The lamellar spacings (λ) were measured from both transverse and longitudinal sections of the samples. The influence of the growth rate (V) on lamellar spacings (λ) and undercoolings (Δ T) was analyzed. λ2V, ΔTλ and ΔTV-0.5 values were determined by using λ,ΔT and V values. Microindentation hardness (HV) was measured from both transverse and longitudinal sections of the specimens. HV values increase with the increasing values of V but decrease with increasing λ values. λ-V, λ - ΔT and λ2V results have been compared with the Jackson–Hunt eutectic model and similar experimental results, HV - V and HV - λ results were also compared with the previous work.

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Directional solidification of Zn-Al-Cu eutectic alloy by the vertical Bridgman method

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb140304007b ◽

2015 ◽

Vol 51 (1) ◽

pp. 67-72 ◽

Cited By ~ 7

Author(s):

U. Büyük ◽

S. Engin ◽

N. Maraşlı

Keyword(s):

Mechanical Properties ◽

Growth Rate ◽

Temperature Gradient ◽

Eutectic Alloy ◽

Temperature Gradients ◽

Directionally Solidified ◽

Constant Growth Rate ◽

Microstructure And Mechanical Properties ◽

Vertical Bridgman ◽

Constant Growth

In the present work, the effect of growth rate and temperature gradient on microstructure and mechanical properties of Zn-7wt.%Al-4wt.%Cu eutectic alloy has been investigated. Alloys prepared under steady-state conditions by vacuumed hot filing furnace. Then, the alloys were directionally solidified upward with different growth rates (V=11.62-230.77 mm/s) at a constant temperature gradient (G=7.17 K/mm) and with different temperature gradients (G=7.17-11.04 K/mm) at a constant growth rate (V=11.62 mm/s) by a Bridgman furnace. The microstructures were observed to be lamellae of Zn, Al and broken lamellae CuZn4 phases from quenched samples. The values of eutectic spacing, microhardness and ultimate tensile strength of alloys were measured. The dependency of the microstructure and mechanical properties on growth rate and temperature gradient were investigated using regression analysis.

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Influence of Growth Rate on Eutectic Spacing, Microhardness, and Ultimate Tensile Strength in the Directionally Solidified Al-Cu-Ni Eutectic Alloy

Metallurgical and Materials Transactions B ◽

10.1007/s11663-018-1404-7 ◽

2018 ◽

Vol 49 (6) ◽

pp. 3293-3305 ◽

Cited By ~ 6

Author(s):

Ümit Bayram ◽

Necmettin Maraşlı

Keyword(s):

Growth Rate ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Eutectic Alloy ◽

Directionally Solidified ◽

Eutectic Spacing

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Morphological Characteristics of W-Nanowires after Selective Etching

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1004-1005.24 ◽

2014 ◽

Vol 1004-1005 ◽

pp. 24-27

Author(s):

Wen Jia Wang ◽

Zhi Long Zhao ◽

Ming Tang ◽

Jian Jun Gao

Keyword(s):

Growth Rate ◽

Temperature Gradient ◽

Directional Solidification ◽

Morphological Characteristics ◽

Selective Dissolution ◽

Stability Diagram ◽

Selective Etching ◽

Directionally Solidified ◽

Solidification Furnace ◽

Nial Matrix

An eutectic NiAl–1.5 at.% W alloy prepared by using directionally solidified (DS)was employed as a source for producing W-nanowires. Several growth rate of 8,15,25/s was respectively used at a temperature gradient of ~240 K/cm in a Bridgman-type directional solidification furnace. A combined stability diagram was applied to predict proper conditions for the selective dissolution of NiAl matrix to get W-wires. Etching in a mixture of HCl:H2O2released parallel aligned W-nanowires with a wire diameter of ~500 nm. Different morphologies, such as nanobelts, lotus-shaped, conical of W-nanowires are obtained at the different conditions.

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