Stabilization grain-size

The microstmctures were studied for phase stability, grain size, interphase connectivity, boundary phases and dislocation stmctures. The examination of a matrix sample tested at... 

Wallwork, 1978). Metallurgical factors also can be important - binary ingot-processed alloys were found to require an A1 concentration for AI2O3 scale formation approximately 4 at.% greater than for oxide dispersion-strengthened (ODS) Fe-Al alloys at 900 °C (Pint et al., 1999c). This reduction was attributed to the fine, oxide dispersion-stabilized grain size of the particular ODS alloys studied. 

Once a sample is acquired, the supplier can begin to prepare the material in the state it will be used. It is particularly important at this stage to stabilize the material (if required) to prevent changes in composition of critical components and to homogenize the material so that all future sub-samples will be as identical as possible. If additional procedures (e.g., reduction of grain size) are needed to prepare the desired material, they should occur at this stage. At this point a preliminary assessment of homogenization should also be made. 

Once the material has been packaged, it must then be checked for uniformity. Any additional characterization of the material, in the form in which it will be distributed (e.g., grain size, color) should be conducted at this stage. Subsequently, the material is analyzed for the analyte(s) of interest for certification purposes, after which the certificate of analysis can be prepared. It is also imperative that a certified reference material or reference material be continually monitored for stability throughout its... 

Table 1.7 Phase composition and grain size of p and y-MgH2 after milling and annealing in Sieverts apparatus during thermal stabilization of the measuring system, at 300, 325, and 350°C under high pressure of hydrogen (4.5 MPa)...

The coarsest grain size of MgH in the composite containing 10 wt%MgH2 is within 35 0 nm range. Present results confirm our previous findings [179] that the formation of true nanostructure in NaBH is difficult to achieve and hence, clearly demonstrate a high structural stability of the compound under heavy deformation conditions imposed by milling. 

Alloys having 15 to 30 wt % Co and very coarse WC grain sizes (up to 20 Jim) have replaced steel rolls in the production of hot-rolled steel rods. Carbide rolls are also well suited for the cold reduction and finishing of strip products in Sendzimii mills where rigidity and dimensional stability are particularly important. The compositions used in these applications have a 5.5 wt % Co and medium WC grain size (1—2 Jim). 

From this explanation for the observed differences in output stability, we may infer that the decomposition potential of any CdX depends on its crystal structure. In view of the results presented here and in ref. 2, it is likely that this potential is a function of exposed crystal face as well. Further insight in those dependences, development of optimal surface treatments, and use of electrodes with optimal grain size, may all be of help in devising strategies to obtain even more stable CdX/S- photoelectrochemical systems. n... 

The DTA measurements exhibit the stability of c-BN at standard conditions. Influences of grain size and purity (oxide content) of the cubic boron nitride crystals on the conversion temperature become obvious. Fine grained samples containing boron oxide show a significantly lower conversion temperature than coarse material (conversion at 900 °C for 1.5-pm c-BN containing boron oxide and 1500 °C for 600-pm pure c-BN). 

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