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After drying, grinding and sieving, the precursor powders were obtained.
Currently, ZrB2 powders are mainly synthesized by carbothermal reduction and self-propagating high-temperature synthesis (SHS).
In SHS processing, the reaction product may also have non-uniform micro-structural characteristics because of temperature non-uniformities as the combustion wave propagates through the samples.

Synthesis of CaAlSiN3:Eu2+ Phosphor via the Self-propagating High Temperature Synthesis Method and Its Optical Properties Shyan-Lung Chung1, 2*, Shu-Chi Huang1 1 Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan, 70101, Republic of China 2 Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan, 70101, Republic of China * slchung@mail.ncku.edu.tw Keywords: nitride phosphor, LED lighting, SHS, combustion synthesis Abstract.
The partical size of the synthesized phosphor after grinding is in several micrometer range as shown in Fig.1.

However when against SiC, it is chiefly controlled by grinding.
Then the powder mixtures were synthesized in argon gas atmosphere by self-propagating high-temperature synthesis (SHS) technique.
Meanwhile, wear debris grinding the surface of MoSi2 make the surface smooth (Fig.5(b)).
It is very smooth and there are only slight grinding track and some small pits on the surface.
However when against SiC, the wear mechanism of MoSi2 is chiefly controlled by grinding.

The self-propagation high-temperature synthesis (SHS) is a main mechanism of mechano-chemistry.
It is reported that a combination reaction which called SHS will occurs in the high-energy ball milling conditions, and heavy metals and high heat capacity materials can react to form stable metal compounds.
Li [17]have investigated the influences of wet grinding on lead stabilization and particle size variation in municipal solid waste incinerator fly ash.
Fig. 5 The result of BCR Conclusions The mechanical grinding method has achieved a good result in treating arsenic sludge.
Dechlorination of polyvinyl chloride by its grinding with KOH and NaOH [J].

Different types of the fine composite powder are obtained by grinding the corresponding compound.
For purpose of enhancing efficiency and making the most use of crushing equipment, the following flow chart shows the grinding system used to gain the fine boride composite powder.
Hou: Elementary research on CaB6 prepared by SHS (Trans Tech Publications, China 2004)

High energy milling was served at room temperature on a planetary ball mill at a rotation speed of 500 rpm with chromium steel grinding balls (12 mm in diameter), and the weight ratio of balls to powders was 10:1.
Fig.1 XRD patterns of milled powder mixtures with different content of Al (a) Ti:Al:C=2:0.5:1; (b) Ti:Al:C=2:1:1; (c) Ti:Al:C=2:1.5:1 So one can deduced that prolonged milling for self-propagating high-temperature synthesis (SHS) can reduce the ignition temperature and a spontaneous mechanically activated SHS reaction is achieved within the milling vial, as called MSR by Yen et al. [12].
It has been shown that if induced reactions by milling are exothermic enough, a self-sustaining reaction similar to SHS can be initiated after a critical milling time.

We also analyzed the modification of this material with the addition of up to 25...30 wt.% Cr3C2 ceramet / PG-US25 obtained by SHS method, leading to an increase of coating hardness (HV100) to 1080 MPa [16].
Ceramet Cr3C2 / PG-US25 was derived using SHS method [17]; composition, properties, and technology for producing this ceramet modifier are described in [16].
Even higher wear resistance during tests - 4.5 times - showed coatings modified with Cr3C2 / PG-US25 ceramet, produced using SHS method.
Changes detected in structure and properties of coatings are explained by simultaneous processes: - formation of new phases (trinary and quaternary boride eutectics, special W2Fe21C6 and W2Co4C carbides); - effect of Charpy; - grinding and dispersion hardening of Fe-Cr-C eutectics during HFC boronation; - Cr3C2 carbide recrystallization with the formation of Cr7C3 needle carbides, etc.
Modification of wear-resistant coatings of Fe-Cr-C system based on the Cr3C2 obtained with help of SHS method.

In this study, twelve NCMPs have been considered in the process selection procedure, namely Water Jet Machining (WJM), Abrasive Jet Machining (AJM), Ultrasonic Machining (USM), Chemical Machining (CHM), Electrochemical Machining (ECM), Electrochemical Grinding (ECG), Electrochemical Honing (ECH), Electrical Discharge Machining (EDM), Wire Electrical Discharge Machining (WEDM), Laser Beam Machining (LBM), Electron Beam Machining (EBM) and Plasma Arc Machining (PAM).
To be able to compare the suitability of alternatives, these attributes are considered to measure the performance of each process: material suitability (MS), shape feature suitability (ShS), surface roughness (SR), surface damage depth (SDD), material removal rate (MRR), corner radii (CR) and taper (Tap).
Using this normalization method implies each cluster has the same TABLE 1 TRANSFORMATION OF THE DIRECT-INFLUENCE TO NORMALIZED FULL-INFLUENCE MATRIX (LEFT TO RIGHT) MS ShS Tol SR SDD MRR CR Tap TF P TW → MS ShS Tol SR SDD MRR CR Tap TF P TW MS 0 0 0 1 1 3 0 0 0 1 1 0.03 0.07 0.08 0.13 0.09 0.26 0.03 0.03 0.03 0.10 0.13 ShS 0 0 0 0 0 0 0 0 1 0 1 0.00 0.01 0.02 0.01 0.00 0.02 0.01 0.01 0.06 0.00 0.07 Tol 0 2 0 2 0 3 3 2 3 0 2 0.03 0.26 0.17 0.21 0.03 0.31 0.24 0.17 0.27 0.05 0.23 SR 1 2 2 0 0 2 0 0 1 1 2 0.08 0.21 0.21 0.09 0.03 0.24 0.06 0.05 0.12 0.10 0.21 SDD 1 1 0 0 0 1 0 0 0 1 0 0.07 0.08 0.03 0.03 0.02 0.10 0.01 0.01 0.01 0.08 0.03 MRR 1 2 2 3 1 0 1 1 0 2 3 0.09 0.25 0.25 0.27 0.09 0.19 0.12 0.11 0.09 0.17 0.29 CR 0 2 2 0 0 1 0 0 1 0 0 0.01 0.17 0.16 0.04 0.01 0.11 0.04 0.03 0.11 0.02 0.05 Tap 0 2 3 0 0 1 0 0 2 0 0 0.01 0.18 0.23 0.06 0.01 0.13 0.06 0.05 0.18 0.02 0.07 TF 0 0 1 0 0 0 1 1 0 0 0 0.00 0.04 0.09 0.02 0.00 0.03 0.08 0.07 0.03 0.01 0.02 P 0 0 1 1 2 3 0 0 0 0 0 0.03
The weighted super matrix is raised to 1000 in this study and the attained weight of criteria are 0.24, 0.23, 0.06, 0.07, 0.03, 0.05, 0.03, 0.04, 0.08, 0.09, and 0.09 for MS, ShS, Tol, SR, SDD, MRR, CR, Tap, TF, P, and TW respectively.
TABLE 3 PERFORMANCE SCORE FOR THE CASE STUDY [4,6,16-22] MS ShS Tol (μ) SR (μ) SDD (μ) MRR (mm3/min) CR (mm) Tap (μ) TF P TW USM 1 5 7.5 0.4 25 300 0 5 3 3 7 AJM 5 3 50 0.5 2.5 0.8 0 5 3 3 5 ECM 5 5 50 1 0 1500 0 1 7 7 1 CHM 3 4 30 2 50 15 0 300 3 1 1 EDM 5 5 15 1 125 800 0 1 7 3 7 EBM 3 5 25 2 250 1.6 0 20 1 3 1 LBM 3 5 25 1 125 0.1 0 50 1 1 1 TABLE 4 SI, QI, RI AND AI VALUES FOR THE CASE STUDY Si Qi Ri Ai Rank USM 0.424 0.236 0.358 0.642 6 AJM 0.463 0.233 0.383 0.617 7 ECM 0.254 0.089 0.196 0.804 2 CHM 0.451 0.118 0.335 0.665 5 EDM 0.271 0.089 0.208 0.792 3 EBM 0.319 0.118 0.249 0.751 4 LBM 0.237 0.118 0.195 0.805 1 As for compromise solution, Opricovic [15] proposed the fraction of 1/(m-1) as the acceptable advantage scale.

Mukasyan2,3, c 1 Institute of Structural Macrokinetics and Material Science Problems, Russian Academy of Sciences, Chernogolovka, 142432, Russia; 2 Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN 46556, USA 3 Center of Functional Nano-Ceramics, National University of Science and Technology, “MISIS”, Moscow 119049, Russia arogachev@ism.ac.ru, bamoukasi@nd.edu, cvadchenko@ism.ac.ru * corresponding author Keywords:Reactive multilayer nanofoils, SHS, combustion synthesis, NiAl, structure formation, macrokinetics.
SHS process in the multilayer nanofoils possesses many unique properties, such as unexpectedly high propagating rate (up to 102 m/s) and extremely short time of reaction and product phase formation (10-7 – 10-6 s).
Understanding of the mechanism of this process has critical significance not only for the theory of SHS, but also for various applications of the reactive nanofilms, e.g., joining of dissimilar materials and items.
In order to improve contacts between layers, careful cleaning of the surfaces of initial foils is used shortly before the cold or hot rolling, e.g., wire-brushing and cleaning with acetone for the cold rolling [8], grinding with abrasive paper for the hot+cold rolling [13], etc.

In this work, we investigate the use of the self-propagating high temperature synthesis method (SHS or combustion synthesis) for the production of CaAlSiN3:Eu2+ phosphor.
The SHS method, originally developed in the former USSR, has been applied to synthesis of various high-temperature materials including ceramics, intermetallics, and composites.
In our previous study [7, 8] , a SHS process was developed for the synthesis of AlN powder by using Al and NaN3 as the reactants.
A typical SEM photograph of the product after grinding and removing NaCl and the residual Si