Xingwei Han

Structure and substructure of martensite in a Ti36.5Ni48.5Hf15 high temperature shape memory alloy

Abstract The martensite structure and substructure in a Ti36.5Ni48.5Hf15 high temperature shape memory alloy were investigated by X-ray diffraction, transmission electron microscopy (TEM) and high resolution electrom microscopy (HREM). The high temperature phase of this shape memory alloy was determined as being CsCl (B2) type structure with a = 0.309 nm. The martensite structure is B19′ type monoclinic structure with a = 0.293 nm, b = 0.411 nm, c = 0.473 nm, β = 100.4° and the space group is P21/m. The substructure in a martensite variant is (001)B19′ compound twins. The orientation relationship between B2 and B19′ was determined to be: [100]B19′ ∥ [100]B2 and (011)B19′ ∥ (001)B2, and the junction plane between two martensite variants was determined to be (011)B19′ ∥ (001)B2 or (1, − 1, 0.64)B19′ ∥ (1 − 1 0)B2.

TEM and HREM study of the interphase interface structure of Ti3Ni4 precipitates and parent phase in an aged TiNi shape memory alloy

Abstract The structures of coherent and semi-coherent interphase interfaces between Ti3Ni4 precipitates and parent phase in different aged Ti 51.5Ni (at.%) shape memory alloy have been studied by means of diffraction contrast analyses in transmission electron microscopy (TEM) and high resolution electron microscopy (HREM). When the alloy was aged at 723 K for 3 h, very small Ti3Ni4 precipitates formed in the matrix with a coherent interface to the parent phase. Very strong strain field was observed in this kind of coherent interface using TEM and HREM. When the alloy was aged at 873 K for 20 h, large Ti3Ni4 precipitates formed in the parent phase matrix possessing a semi-coherent interface. The dislocation networks were observed in the semi-coherent interface. The Burgers vectors of these sets of dislocations are determined to be 〈111〉B2 and 〈200〉B2 types. Very weak strain field was observed in this kind of interface.

Design and development of optoelectronic detecting system for space debris

The paper presents the design and development of a medium-size optoelectronic detecting telescope which will be used for space objects and debris detection. First, the paper introduces the work principle of the detecting system. Then it gives out the design scheme, the main syetem parameters and the fulfillment of the optoelectronic detecting system. And last it shows some results of the system to track the space objects.

Singlet pairing gaps of neutrons and protons in hyperonic neutron stars

The

The control system of KHz SLR under Windows' XP environment

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Detection algorithm and implement of space objects in star background

nucleonic superfluids are investigated within the relativistic mean-field model and Bardeen-Cooper-Schrieffer theory in hyperonic neutron stars. The

Research on pointing model of telescope based on SLR tracking data

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Experimental visibility of KHz laser beam at daylight

pairing gaps of neutrons and protons are calculated based on the Reid soft-core interaction as the nucleon-nucleon interaction. We have studied particularly the influence of hyperons degrees of freedom on the

KHz SLR and daylight tracking at Changchun

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Preliminary performance test and comparison of several photodetectors as start detector in SLR system

nucleonic pairing gap in neutron star matter. It is found that the appearance of hyperons has little impact on baryonic density range and size for the