Abstract An Al 2 O 3 –13 wt% TiO composite ceramic coating was prepared on the TiAl alloy surface by plasma spraying and laser remelting combined technique. The morphology, microstructure, phase composition of were analyzed scanning electron microscopy, energy disperse spectroscopy, x-ray diffraction. bonding strength, microhardness, wear resistance, erosion thermal shock resistance also tested...

In this letter we announce rigorous results that elucidate the relation between metastable states and low-lying eigenvalues in Markov chains in a much more general setting and with considerable greater precision as was so far available. This includes a sharp uncertainty principle relating all low-lying eigenvalues to mean times of metastable transitions, a relation between the support of eigenf...

Metastable austenitic stainless steels (MASS) are widely used in various industrial applications due to their exceptional compromise between mechanical properties and corrosion resistance. However, the of these materials can be further enhanced by surface treatments. This paper reviews treatment methodologies improve MASS, with particular attention laser The effects treatments on microstructure...

2014 We consider an Ising spin glass chain at 0 temperature. The moments of the total number of metastable states and the typical number of metastable states at a given magnetization are calculated. We find that for all magnetizations less than or equal to mmax = 0.446042... there is an exponentially large number of metastable states. For magnetizations larger than mmax, there are no metastable...

Hydrostatic pressure effects on pitting initiation and propagation in X70 steel are investigated by evaluating metastable pitting probability using electrochemical methods and immersion corrosion tests in containing chlorine ion solution. Potentiodynamic tests indicated that hydrostatic pressure can decrease the breakdown potential and lead to a reduced transpassivity region. Metastable test re...

We report on the fragmentation of ionized pyridine (C(5)H(5)N) molecules by focused 50 fs, 800 nm laser pulses. Such ionization produces several metastable ionic states that fragment within the field-free drift region of a reflectron-type time of flight mass spectrometer, with one particular metastable dissociation being the leading fragmentation process. Because the time of flight is no longer...

The space of metastable materials offers promising new design opportunities for next-generation technological materials, such as complex oxides, semiconductors, pharmaceuticals, steels, and beyond. Although metastable phases are ubiquitous in both nature and technology, only a heuristic understanding of their underlying thermodynamics exists. We report a large-scale data-mining study of the Mat...

Metastable phases may be spontaneously formed from other metastable phases through nucleation. Here we demonstrate the spontaneous formation of a metastable phase from an unstable equilibrium by spinodal decomposition, which leads to a transient coexistence of stable and metastable phases. This phenomenon is generic within the recently introduced scenario of the landscape-inversion phase transi...

We investigate the metastable behaviour of reversible Markov chains on countable infinite state spaces. Based on a definition of metastable sets, we compute precisely the mean exit time from a metastable set. Under additional size and regularity properties of metastable sets, we establish asymptotic sharp estimates on the Poincaré and logarithmic Sobolev constant. The main ingredient are capaci...