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Austenite reversion as afunction of deformation processes has been investigated in an 18 wt-%Ni 350 grade maraging steel. The results reported show that the degree and type of deformation imparted to martensite influences the amount of reverted austenite obtained following aging. The validity of the X -ray diffraction technique in determining the reverted austenite content is discussed with reference to texture incorporated during cold forming. Transmission electron microscopy was carried out to study the partitioning of solute during austenite reversion. specimens were deformed by either cold rolling or flow turning. Specimens of size lOx 10 mm were cut from the deformed sheets for heat treatment and subsequent determination of austenite content. Thin foils were obtained from the heat treated specimens and were examined in a Jeol2000FX scanning transmission electron microscope, equipped with an energy dispersive X-ray (EDX) spectrometer to facilitate chemical analysis. DETERMINATION OF AUSTENITEThe X-ray diffraction method of quantitative phase analysis was applied to determine the volume percentage of reverted austenite (a). The direct comparison method of Averbach and Cohen 9 was employed, which does not require a standard sample of known austenite content because the required reference line is obtained from the martensite (m). The basic equation relating the diffracted intensity and volume fraction of austenite Jt: in an alloy containing only austenite and marfensite of the same chemical composition is as follows 10 Jt: = volume fraction of austenite la, 1m = integrated intensity of martensite and austenite, respectively, measured from X-ray spectrum Ra, Rm = theoretical peak intensities of austenite and martensite, respectively, which in turn depend on hkl, Bragg angle 8, structure factor F, Lorentz polarisation L, volume of unit cell v, multiplicity factor p, and temperature factor exp(-2M) X..:ray peaks from a deformed specimen containing reverted austenite were observed at {IIIL, {IIO}m, {200}a, {200}m, {220}a, and {220}m planes (Fig. 2). Thus when R factors are calculated for these planes the volume fraction of austenite can be calculated from equation (1). These R values were calculated for 18 % Ni 350 maraging steel. The equation for

Study wear resistance for heat treatment of Ni-B-CNT electroless coatings. Different concentrations for CNT (0 ,0.35 and 0.7 g/l Ni-B-CNT composite coatings deposition on 4340 steel. After the procedure of coating, all samples were heat treatment. The test wear of a coating was valued with pin on disk technique. Preparation of Ni–B–CNT electroless coatings are with using nickel chloride in alkaline bath, borohydride and Multi walled carbon nanotubes. characterization with FESEM, micro hardness, XRD and surface roughness. Study for surfaces of worn with EDS and FESEM. Micro hardness results are show that the larger hardness1010 HV is gained by heat treatment for coating (Ni-B- 0.35 g/L CNT) because of concentration CNT caused structure conversion for coating Ni-B from amorphous to crystalline. Also, CNT prevent maximum heat production and decrease of the friction coefficient during test wear. CNT aggregation was noted result the presence for more particles (Ni-B - 0.7g/l CNT) that occur create roughness and also lead to increase in rate of wear because of big particles with weakly joined in matrix of Ni.

Polarisation methods, and Open circuit potential measurements have been utilized to evaluate the impact of heat remediation on the corrosion characteristics of CuAlNi shape memory alloy in 3.5 percent NaCl solutions. CuAlNi alloy specimens were investigated in their as-sintered condition and following a thermal remediation processing that included annealing at 900 °C for 60 min associated with water quenching, and 200-degree centigrade for 30 hrs. and rapid cooling in iced water. The enhancement in polarisation resistance and reduction in corrosion rate of heat-treated CuAlNi alloy further suggests that heat remediation has a positive effect on CuAlNi alloy corrosion resistance. After measurements of polarisation, optical microscopy, SEM/EDX, and XRD examination of specimen surfaces reveal the presence of corrosion damage on the electrode surfaces, with CuCl2, AlCl3, and Cu2Cl (OH)3 compounds as surface corrosion products..