The process of cast explosive solidification molding has been dynamic monitored by multi-channel ultrasonic transmission method. It presents the regular pattern of ultrasonic attenuation, velocity and waveform in this process. The results show that velocity values and waveform are relative to solidification speed and physical characterization on the phase border, and ultrasonic attenuation is r...

the micro-segregation in binary al-cu alloys containing 2.2, 3.7, and 4.8 wt.% copper was investigated by differential thermal analysis (dta) and numerical modeling. for this purpose, the alloys were melted using a dta furnace with the capability of quenching samples during solidification. the melted samples were cooled at 0.008 and 0.083 k/s and subsequently quenched from predetermined tempera...

We give a general phenomenological description of the steady-state 1D front propagation problem in two cases: the solidification of a pure material and the isothermal solidification of two-component dilute alloys. The solidification of a pure material is controlled by the heat transport in the bulk and the interface kinetics. The isothermal solidification of two-component alloys is controlled b...

Chaput Kevin J. Ph.D., Purdue University, May 2015. Near-Congruent Solidification of Castings. Major Professor: Kevin Trumble. A study on the microstructure development of as-cast Cu-Mn alloys based around the congruent minimum at 34.6 wt % Mn and 873 oC was performed. Initially, this was to evaluate the alloy as an alternative to wide freezing range Pb and Sn bronzes that are plagued with poro...

Using scanning and transmission electron microscopy, we studied silicon particles formed during the solidification of Al-7%Si alloy when different modifying mixtures were introduced into the melt: (1) a mixture of ultrafine powders Na3AlF6 + K2ZrF6 + TiO2 + ZrO2; (2) K2ZrF6; and (3) the flux Arsal. By differential scanning calorimetry, it was established that modifying mixtures significantly in...

We propose a scheme for simulation of the solute-driven dendritic solidification which accounts for the flows of liquid and motion of growing dendrites. The scheme is based on the multiphase-field method for calculating the solidification and the lattice Boltzmann method to simulate the fluid flows. Motion and rotation of solid grains is possible.

Two distinct and novel formalisms for deriving exact closed solutions of a class of variable-coefficient differential-difference equations arising from a plate solidification problem are introduced. Thereupon, exact closed traveling wave and similarity solutions to the plate solidification problem are obtained for some special cases of time-varying plate surface temperature.

simulations of morphological instabilities and dendritic solidification is given first, in order to put our work into perWe present a front-tracking method to simulate time dependent two-dimensional dendritic solidification of pure substances. The spective. method is based on a finite difference approximation of the heat The process of solidification of a pure substance can equation and explici...

Cracking is a major concern in welding aluminum alloys. Although weld solidification cracks can be eliminated through addition of filler alloy, the additives modify the alloy or base-metal constituents and may not always be desirable. High-energy beam processes, such as electron-beam welding, that result in minimal heat input reduce crack sensitivity, but their high cost limits their applicatio...