Research of Ti2AIC/TiAI(Nb, B) Composites Based on Multi-fractal Spectrum

摘要

Spark plasma sintering (SPS) technology was used in-situ to fabricate the Ti_2AlC/TiAl (Nb, B) composites. And the composites were treated by rapid heat treatment, which had many advantages, such as heating-up quickly, short holding time and relatively slow cooling. The hidden relationship between images could be reflected by Multi-fractal spectrum, which also could show irregularity apparently. In this paper, the SEM images which fabricated after rapid heat treatment were researched by multifractals. And the parameter was calculated by MATLAB through anglicizing the multi-fractal spectrum theory. There was only small fluctuate between lnχq(r) and lnr when r=0.00625, and lnχq(r) and 1nr had well linear relationship in spite of the value of q. After the rapid heat treatment at T=1403 K, the correlation coefficient between τ(q) and q reached 99.99% . The trend of D (q) and q turned to be gently, and the fracture appeared uniformity, and these SEM images were single fractures, τ (q) and q show nonlinear relationship in q∈[-3,-1], and there was one observe steep. The clock shape relationship between the a and f(α) revealed good symmetry of spectrum, wider spectral width, uneven distribution of the fracture, multi-fractal feature clearly, and obvious characteristic of multi-fractal.