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BMGs have homogeneously long-range disordered structures[21, 22] without defects like grain boundaries or dislocations, that could slightly modify corrosion resistance of Zr-based alloys compared with their crystalline counterparts[23, 24], but prominent enhancement of corrosion resistance of these alloys mainly depended on the electrochemical properties of the elements instead of their structure[10, 25, 26].
Due to a lack of crystalline defects like dislocations or grain boundaries, structurally homogeneous BMGs could form a uniform passive film without nucleation sites for corrosion.
Many relative studies [10, 11]demonstrated that a number of Zr as well as some other elements was detected by EDX or AES on uncorroded region of alloy surface of Zr-Cu-Al-Ni system alloys after polarization, indicating that uncorroded region mainly consisted of ZrO which formed passive film.

There are number of hazardous wastes used in stabilization/solidification (S/S) technique.
Additives pH CEC EC Gs Grain Size (%) Chemical Analysis (meq/100g) (mS/cm) Sand Silt Clay SiO2 Al2O3 Fe2O3 CaO MgO P2O3 K2O SO3 LoI CO2 Lime 12,60 16,43 6.29 2,45 5 75 20 2,72 0,37 0,25 63,88 4,00 0,01 0.06 0.02 27,5 10,52 Cement 12,63 21,74 4.97 3,19 6 58 36 20,35 5,19 3,34 64,56 1,52 0,07 0.70 2.04 1,3 4,86 Zeolite 8,20 165,17 2.09 2,63 2 74 24 71,39 13,30 0.94 2.74 0,71 0,03 3.69 0.01 6,25 0,96 Na-Bentonite 9,50 90,22 2,69 2,60 - 12 88 59,49 18,06 4,14 3,72 2,42 0,11 0,91 0,01 8,02 1,31 Natural Soil 8,14 15,22 2,54 2,56 7 63 30 65,36 14,29 4,31 1,20 1,14 0,09 1,47 0,02 7,43 1,45 CEC: Cation Exchange Capacity; EC: Electrical Conductivity; Gs: Specific Gravity; LoI: Loss on Ignition Experimental Results and Discussion Backfill Materials: Unconfined compression strength (UCS), permeability, leachate test, California Bearing Ratio (CBR), freezing and thawing tests are most popular indicator of stabilization efficiency.
Technical specifications of CCW concrete blocks (after 28 days curing) Parameter Description Size 300 x 200 x 150 mm Compressive strength 40-50 kg/cm 2 Capillarity 4,85 10-6 cm 2/s Water absorption after 24 hours Less than 6 % by weight of block Mix Proportion 1:7 (1 part cement:7 parts sum graded CCTW) Density 1900 kg/m 3 Grain Size Distributions for Concrete Block (%) 4.8-8.0 mm CCTW 2.0-4.8 mm CCTW 0.4-2.0 mm CCTW Crushed Aggregates 0.2 mm Sand 10 % 20 % 20 % %35 15 % Improving Expansive Soil Materials: Relationship between the free swelling percent and swelling pressure are shown in Figure 3.

The effects of alloying elements such as Mo, Sn, Zr, Nb and working-rates, solid solution and aging treatment on the mechanical properties and microstructure of nearβtype biomedical Ti alloys based on Ti-Nb-Zr system were investigated. . 2 Experimental procedures 7 kinds of nearβTi alloy were designed which Mo equivalences (Moeq) ranged from 3.6~10.2 and numbered 3#~9# separately. 0 grade Ti sponge, pure Zr bar (4×2mm, 99.7wt%), pure Sn bar (5×2mm, 99.9wt%), pure Mo powder and Nb53Ti47 intermediate alloy were used as raw materials.
Thus the aging leads to dispersion strengthening and fine grain strengthening of near β alloys.
After solid solution and aging treatment (STA), The βMS or α' start to dissolve and then transform to large quantities of finer secondary α phase (αs) with dot or needle shape in β matrix, which result in dispersion strengthening and fine grain strengthening.

This is associated with the Cr depletion around the grain boundaries.
Partridge et al. [2] analyzed SG tube failure data for a number of plants in terms of whether or not H3BO3 mitigates IGA/SCC.
Crack initiation and propagation appeared as IGSCC along the grain boundaries.

Introduction Magnesium alloys present a number of interesting properties, such as high specific strength, good castability, low density, etc.
The as-cast microstructures of CaO added AZ31 Mg alloys are characterized by magnesium grains, grain boundary eutectic phase of Mg17Al12 and Al2Ca.

It was found from Fig.2 that neither the grain size nor the dendrite arm spacing as well as their shapes were obviously changed by various homogenizing treatments.
There were a lot of black dots on grain boundaries and interdendritic areas in the as-cast (Fig.1) and the homogenized microstructures at 360ºC even after 24h heating(Fig.2, d), some dots segregated to form black areas.
The black dots in the samples homogenized at 400ºC and 440ºC were much less than those in the sample homogenized at 360ºC, and with the heating time increase, these dots become to be less in number but big in size, which is more obviously at 440ºC than at 400ºC (Fig.2, e to h, i to l). 400� m Fig.2 Microstructures of ZM21 alloy after homogenizing treatments a: 36��™�� b: 36��™��� c: 36��™��� d: 36��™��� e: 400�™�� f: 40��™��� g: 40��™��� h: 40��™��� i: 44��™�� j: 44��™��� k: 44��™��� l: 44��™��� Fig.3 Macrostructure of samples after homogenization( 360�� (Electrolytic polishing, 2 voltage, 10s, phosphoric acid 33.3% + alcohol 66.7%) 400wm 400wm 400wm 36��™��� 36��™�� 400wm 36��™��� 36��™��� Fig.4 was the micro-hardness vs homogenizing time curve and average relative error of micro-hardness vs homogenizing temperature curve, every micro-hardness value was the average of 5 measuring points, the diversity of

Thus there have been number of investigations on Ti-Zr-Ni alloys aiming for high temperature shape memory alloys [3-9].
These precipitates are uniformly distributed through out the B2 grains and the region near the grain boundaries as well as the interphase boundaries with Laves phase (Ti, Zr)2Ni, which is occasionally found.

Increasing the milling time to 20 h increased the number of hard NbC particles mechanically aggregated to iron particles, thus improving the distribution of the reinforcing phase and the overall property homogenization of the composite.
Increasing the temperature, grain boundary and volumetric diffusion were activated affecting the slope of the dilatometric curve (~800 °C)
It consists of regular grains of the matrix surrounded by carbide particles and solidified liquid phase.

A large number of island texture appeared at Mg base side.
The strength of the joints are controlled by the composition, grain size and properties of the phases formed during the bonding process.
The increasing amount and grain size of IMCs at the interface with the extended holding time lead to the increasing microhardness values of the layers in the interfacial zone.

The wear behaviour of these alloys depend upon number of mechanical properties, microstructure in addition to the service conditions such as load, sliding speed, temperature, environment and counter surface [3].
Maximum addition of 0.7% Mg to A356 alloy results in conversion of unmodified acicular silicon to lamellar, a partially rounded and even a fibrous structure while, the a-Al grains remain dendrites.
Gruzleski, Grain refinement mechanisms of hypoeutectic Al-Si alloys, Acta Mater. 44(9) (1996), 3749-3760