Surface relief caused by the formation of lower bainite in an Fe-C-Si-Mn alloy has been investigated by STM. It was discovered that the subunit which is the lowest structural unit observed by TEM is actually made up of sub-subunits. The surface relief due to the formation of sub-subunit is tent-shaped, and of a non-IPS type, which indicates that the sub-subunit cannot be formed by shear. The height of relief is 60-140nm, and the maximum shape deformation is ca. 0.23. The multi-layer structure of bainite and the effect of carbon and silicon on the fine structure of bainite can be interpreted by sympathetic nucleation-ledgewise growth mechanism.

The habit planes of martensite variants in Cu-based shape memory alloys are calculated with phenomenological crystallographic theory and the probable types of inter-variant boundaries are analysed with group theory. The results show that there are four kinds of twin relationships, i.e., reflection twin, 180°rotation twin, 120° rotation twin, and 90°rotation twin.

The Ni3Al+Ni7HfZ unidirectionally soliditied lamellar eutectic has been studied to improve the transversal ductility and interface-thermal-stability of the ordinary eutectic composites in situ. The microstructure of Ni-5.8Al-32Hf (mass fraction,%) alloy was investigated in detail by means of metallography, transmission electron microscopy (TEM) and electron probe. The solidification behaviour of Ni3Al+Ni7Hf2 eutectic alloy was investigated at different temperature gradient (G) and solidilication rate (R). The results show that Ni-5.8Al-32Hf alloy with Ni3Al+Ni7Hf2 eutectic structure is considered to be the proper compositon. Some brittle β-NiAl phase in the alloy can be avoided by decreasing soliditied rate. Melting range of the alloy above mentioned composition is 41℃ determined by DTA. The critical value of G/R for NisAl+Ni7Hf2 eutectic is 5×105 ℃·s/cm2, and the lamellar Ni3Al+Ni7Hf2 eutectic aligned parallel to the direction of solidilication was obtained under R=5μm/s and G=250℃/cm.

Monotonic and cyclic plastic deformation behaviour and microscopic mechanism of zircaloy-4 under biaxial tension loading along different loading paths were investigated. The results show that an obvious stress delay appears in comparison with the strain increment vector after the turning point of a strain path. The equivalent stress suddenly drops then increases, and the firstly softening and subsequently haxdening degrees are related to the turning angle values,the path length and turning direction. Therefore, the influence of the deformation history and the coupled effects among strain components on the response can not be neglected. By TEM, the deformed dislocation configurations are parallel dislocation lines in uniaxial tension with constraint condition, a lot of free dislocation lines between channeals in double-triangle, and embryonic cells in elliptical and circular loading, respectively. The correlation between macroscopic deformation behaviour and microscopic deformation structure is discussed, finally.

By using AP-FIM the effects of addition of B on the order degree and field ion image contrast of Ni3Al have been investigated. There are many Ni-rich regions in Ni3Al without B. The addition of B can result in the preferential orientation of Ni3Al. As content of B increases, the number of anti-site Al atom increases and the order degree of Ni3Al decreases.The latter is also one of the reasons of the ductility improvement in Ni3Al at room temperature.

The effect of strain rate on the tensile yield strength and elongation of titanium aluminide has been studied. The alloy has a composition of Ti-47Al-2Mn-2Nb-0.8TiB2 (atomic fraction, %; volume fraction, %, only for TiB2) and near lamellar dricrostructure. It manifests brittle-to-ductile transition (BDT) at elevated temperature and its brittle-to-ductile transition temperature (TBDT) is positively sensitive to the strain rate. The addition of boron lowers the TBDT considerably, and the corresponding activation energy of BDT decreases to 256 kJ/mol, which is less than that of the alloy without boron (TiB2), but approximates the self-diffusion activation energy of atoms in the TiAl alloy. From additional fractography analysis and theoretical estimation, it is suggested that the BDT course of 7 titanium aluminide with the addition of boron (TiB2) is controlled by dislocation climbing.

The toughness and microstructure of CGHAZ of Ti microalloyed steel were investigated by means of OM, TEM of carbon extraction replica and metal foil, and series charpy impact testing. The results showed that with the increase of cooling time (t8/5), the austenite grain coarsening was not serious, the microstructure varied from a mixture comprised mainly of upper bainite to a mixture comprised mainly of acicular ferrite, the pearlite changed from a non-lamellar structure to a lamellar structure, and the M-A constituent changed from a elongated shape to a massive shape, therefore the toughness of CGHAZ of Ti microalloyed steel increased. It was also found that the great majority of particles in the CGHAZ are TiN, and small amount are Ti3Al, AlN and MnS.

The continuous cooling transformation (CCT) diagrams of austenite in various states for steel P20 were constructed by means of the combined method of dilatometry and metallography. The influence of deformation process on the transformation behaviour and microstructure was investigated. The thermomechanically processed austenite was more stable than that treated by conventional hardening process. Polygonal ferrite transformation did not occur during continuous cooling at rate ranging from 0.2℃/s to 0.02℃/s. Deformed austenite caused itself mechanical stabilization, hence retarded the bainitic transformation to lower temperature.The experlinental results manifest that steel P20 treated by slowly continuous cooling through bainitic transformation region after hot rolling can produce granular microstructure and reveal hardness of HRC 35-38.

Low cyclic fitigue (LCF) behaviour of a directionally solidified (DS) nickel-base superalloy at high temperature was studied in this paper. Its cyclic stress-strain curve and strain-life curve were obtained. Manson-Coffin equation was obtained through least-square procedure. By macro-and micro-scopy observation, it was discovered that cracks initiated predominantly at interior and near-surface defects. Once formed, cracks propagated transgranularly and normal to the loading direction.

The partition coefficients of elements during solidification were measured to investigate the forming mechanism of the solidification structure in Fe-C-5 Cr-5Mo-5W-V alloy. The changing of the alloy liquid composition with solidification process was analysed by calculation and experiment. The partition behaviour of alloy elements during solidification and the relationship between the change of liquid phase composition and solidilication reaction were determiend. After primary crystal had been formed in the alloy the eutectic reactions carried in the sequences of γ+MC, γ+M2C and γ+M7C3 when C content was lower than 3.0%, and in the sequences of γ+MC, γ+M7C3 and γ+M2C when C content was higher than 3.0%. The longer the distance between the alloy composition point and eutectic point, the more the primary crystal phase formed, on the contrary, the more eutectic structures formed. The eutectic reaction L→γ+MC occuring at low C content was beneficial to obtain more eutectic MC.

Electrochemical charge-discharge-cycling measurements were made on electrode samples prepared from alloys of the same composition with different solidification rates,and their discharge capacity, cycle stability, discharge voltage characteristics were compared.High solidification rates could improve greatly the stability and discharge voltage property, but also lead to a decrease in capacity, especially the high discharge rate capability. All alloys in as-quenched state were generally much more difficult to activate completely.

The equations of the central atoms (CA) model are simplified and derivatived in this paper. The new equations are similiar to the equations of ordinary thermodynamic models used usually, the static value difference between the i atomic state and is not need in proportion to, where i denoted there are i atoms B in the nearest neibouring shell of central atom or. The total of the probability of every atomic state, Pa equals to the reciprocal of activity coefficient of component a. The Ag-Cu diagram and its thermodynamic properties are calculated by this model, and the results coincide well with experimental values.

The method to determine the activity in slags by means of the slag-metal equilibria was discussed. Determining the activity of CaO in the CaO-SiO2-Al2O3, CaO-SiO2-MgO and CaO-B2O3 systems was used as some examples. The correct selecting the test temperature and having enough time for equilibria are key factors for successful determination. Previous preparation of suitable related alloys and mother slags is necessary to test.

Polycrystalline diamond films were deposited on cemented carbide substrates using direct current plasma jet chemical vapor deposition (CVD) method. The structures, morphologies and compositions of diamond films and film-substrate interfaces have been characterized by XRD, Raman spectroscopy, SEM and EPMA. The results show that the faceted type diamond film with high crystallinity has good quality, high purity and excellent adhesion. Its film-substrate interface is dense and tortuous, and there is a significant mechanical anchoring effect between diamond film and substrate. The morphologies of substrate surfaces change greatly after deposition, there is several tens of microns in thickness cobalt-etched layer sequentially etched by plasma. The plasma etching leads to the cobalt-etched layer much rougher, which is beneficial to the diamond nucleation.

The concept of texture configuration entropy is introduced into the computer simulation on texture evolution of polycrystalline films. The grain orientation distribution in thin films is quantitatively determined by a new simple model. As an example, inverse pole figures of polycrystalline aluminum thin films are simulated by considering the change of texture configuration entropy and another orientation dependent driving forces during grain growth, such as surface energy and strain energy. The physical mechanisms affecting the texture evolution of polycrystalline thin films are discussed.

A novel electrodeposited Ni-La2O3 composite coating with a superior oxidation resistance has been applied as a protective coating of γ-TiAl intermetallic compound against high temperature through a technique of the codepostion of tiny La2O3 particles with nickel onto to the surface of the intermetallic. Both experimental results of isothermal okidation at 1000℃ for 48h and cyclic oxidation at 900℃ for 330 h showed that the poor oxidation resistance of the intermetallics was significantly improved after the intermetallics was coated with the composite film. SEM/EDX and EPMA results indicated that the preferentially formed La2O3-modified NiO layer on the Ni-La2O3 electrodeposited composite film could block growth of TiO2 out of the surface scale and favor the formation of two continuous protective Al2O3 layers. The two alumina layers, one beneath the La2O3-modified NiO layer and the other close to the subsurface zone in the substrate, are responsible for maintenance of the superior oxidation resistance of the coated γ-TiAl during the long-term thermal cycling.

The effect of several sputtered coatings on oxidation resistance and mechanical properties of Ti60 alloy was investigated. Sputtered pure Al, Ti-36Al, Ni-16Cr-2.SAl (mass fraction, %) coatings and reactively-sputtered Al2O3 film were effective in decreasing the oxidation rate of Ti60 alloy. Al2O3 and TiAl coatings exhibited a better effect than Al and NiCrAl coatings from the point of view of coating compatiability to substrate. The tensile test after 100 h exposure at 600℃ in air also showed that Ti60 alloy with Al2O3 and Toil coatings exhibited a higher ductility than that with Al and NiCrAl coatings. TiAlCr coating exhibits a better combination of oxidation resistance and compatiability to substrate than the above investigated coatings.

Ceramic powders of Al2O3 and TiC are coated with a layer of cobalt. Successfully the hot-pressed Al2O3-TiC-Co(ATC) modified ceramic possesses improved mechanical properties. Especially its bending strength and fracture toughness are much higher than that of Al2O3-TiC (AT30) ceramic. The abrasion wear behaviour, mechanisms and wear resistance of ATC and AT30 ceramics are compared and studied. The results show that ATC ceramic possesses driproved wear resistance.