Zhi Qiang Jiang

Integration of close Range Photogrammetry and Structured Light Scanner for Cultural Heritage Documentation

This paper proposes an integrated three-dimensional(3D) shape acquiring and digitizing method for cultural heritage documentation by combining industrial close range photogrammetry and structured light scan techniques. The operation principle is introduced, the process of raw data acquisition and data post-processing are presented . A 2.5m high ancient Buddha sculpture of over 1500 years old located in Qingyang, China was measured and modeled to test the availability and reliability of the proposed system. Compare to conventional 3D digitizing methods, the proposed system can potentially meet a number of specific needs in the field of cultural heritage documentation, it is more flexible, low cost, less field work, capable of grabbing the 3D shape of large objects, meanwhile recording accurate detail information of local area, without physically contacting with object surface.

Influences of RE-Ti Composite Modification on the Structure and Properties of W6Mo5Cr4V2 Alloy

The structural change and properties of W6Mo5Cr4V2 alloy (M2 steel) inoculated by addition of rare earth (RE)-Ti were investigated. The results indicated that the impact toughness and fracture toughness were increased distinctly due to network eutectic carbides elimination, matrix structure refinement, and well-distribution of eutectic carbides. The hardness of modified M2 steel hardly changed. In addition, the high temperature wear resistance was improved.

Investigations on the Crack of Centrifugal Casting High-Speed Steel Rolls

A study on solidification process of centrifugal cast high-speed steel (HSS) rolls and the crack forming condition is discussed. The result was represented that the crack forming was because of the solidification layer strength of HSS roll was low, and a clearance between the solidification layer and the mould, and the solidification layer of HSS roll could not endure a large centrifugal pressure. In common centrifugal casting, the free solidification constriction of HSS rolls was difficult, which accelerated the crack propagation. The appearance of mesosphere and axial solidification was unfavorable to obtaining the compact roll structures, which accelerated HSS rolls to crack.

The Damage Evolution of the Flange Repaired Reinforcement Laminates

The Finite Element Model (FEM) study of the flange repaired cut-out laminates were carried out in this work. The FEM studies on the reinforcement and unrepaired structure is focused on simulation of the tensile test, damage evolution and the predicted failure loading. The test results indicated that the strain value decreased as the size of load is. The simulation results show that the tensile strength of the reinforcement is larger than that is unrepaired. Compared the results of damage evolution with four kinds damage criterion, the major failure model is matrix cracking under transverse tension appeared in the layers.

Effect of Ga on Microstructure and Mechanical Properties of the TiCu-Base Nano/Ultrafine Bimodal Structured Alloy

The effects of 2at.% Ga addition on the microstructure and mechanical properties of the TiCu-base nano/ultrafine bimodal structured alloy were investigated systematically through XRD, OM, compressive test and SEM. The results showed that constitutional phases were changed from bcc -Ti(M) to unknown nanostructure + bcc -Ti(M), content of nanostructured matrix is increased, the calculated mean crystalline size was decreased from 12.6 to 11.7nm, and also, the yield and maximum strengths and plasticity were enhanced markedly. The reasons, which caused these phenomenons, were discussed.

Nanaostructure-Dendrite Ti44Cu46Co4Zr6 Composite with Excellent Mechanical Properties

New bulk nanostructure-dendrite Ti44Cu46Co4Zr6 composite with excellent mechanical properties has been fabricated by using copper molder casting through systematic alloy design from binary Ti50Cu50. The results showed that the micro-scaled β-Ti (M) solid solution embedding on the nanostructured matrix, which resulted in the excellent mechanical properties: high fracture strength (σf=2278 MPa) and good ductility (εp=9.01%) under quasi-static compression.

Development of a 3D Full-Field Monitoring System for Large-Scale Static Deformation Based on close Range Photogrammetry

A non-contact deformation measurement method is proposed for monitoring the 3D full-field static deformation of large-scale structures under loads, which could not be achieved by traditional displacement sensors and resistance strain gauges. This method is based on the close range photogrammetry technology. By tracking and comparing the 3D coordinates of the targets between different epoch, the load–deformation diagram in 3D form for the whole large-scale structure is obtained, which is valuable for further mechanical behavior analysis. Real-scale power transmission tower experiment shows that the proposed method can fulfill the efficiency and accuracy requirement in large-scale full-field deformation monitoring task

A Study of the Installation and Adjustment Analysis Approach for Shaft Coupling Device with CAD

The shaft coupling device (SCD) is the key mechanical components for the connection between motor and driving device, its fixing progress in installation and adjustment analysis is a very important. In this paper, the several deviation types appeared in installation of SCD were analyze in detail. The principle and method on the initial alignment, the exact alignment within the absence axial movement, and the precise alignment within the axial movement of coupling were studied. A deviation analysis approach model on the precise alignment at the axial movement of coupling in the vertical and horizontal plane was established, and a method of analyzing and calculating the fixing progress and the adjustment of SCD with computer aided design was realized. Finally, an illustrative example to calculate the installation and adjustment analysis demonstrated application and examined its effectiveness was proposed. It is not only fair and reasonable conclusions, but also the improvable accuracy on rapid data process can be acquired clearly.

A Study on the Effects of Heat Treatment to the High-Carbon HSS Roll

High-carbon high-speed steels (HSS) are extremely abrasion resistant materials due to their high hardness MC type carbide and high hardness martensitic matrix. Different microstructures and mechanical behaviours were obtained after the quenching and tempering temperatures of HSS roll were changed. With air cooling and sodium silicate quenching, when the austenitizing temperature reaches 1273K, the metal matrix all transforms into the martensite, Afterwards, the eutectic carbides dissolve ceaselessly into the metal matrix and its continuous network distribution changes into broken network. The peak hardness temperature of high-carbon HSS is around 1323K, and the second hardening temperature is around 793K. No significant change in tensile strength and elongation percentage was observed unless the tempering temperature is beyond 753K. The tensile strength is increased obviously and the elongation percentage is decreased slightly beyond 753K. However, the tensile strength is decreased and the elongation percentage is increased when the temp exceeds 813K. The high-carbon HSS roll presents excellent abrasion resistance at 793K-813K.

Influence of Heat Treatment on Structures and Mechanical Properties of Cast Fe-B-C Alloy

Influence of quenching temperature and cooling speed on the structures and properties of cast Fe-B-C alloy containing more than 1.0%B and lower than 0.2%C was researched. The results showed that the structures of Fe-B-C cast alloy changed from a great of pearlite + a small of martensite a great of martensite + a small of pearlite martensite and the hardness increased with the increase of quenching cooling speed. In the condition of water cooling, higher or lower quenching temperatures were not advantageous to obtaining single martensite. Quenching at 950~1000oC, cast Fe-B-C alloy could obtain the compound structures of fine lath martensite. The hardness and impact toughness of cast Fe-B-C alloy excelled 55HRC and 15J/cm2 respectively.