Experimental Research on Hot Working Property of Monel K-500 Alloy

Monel K-500 alloy is an important nickel-based corrosion resistant material with excellent corrosion resistant ability in various corrosion circumstances (include electrochemical and chemical corrosion) and good mechanical properties. However, Monel K-500 alloy is also a sensitive material to high temperature. Hot working process has significant effect on its working character and quality. In view of existing problems in domestic manufacturing enterprises, some experiments were carried out in different working temperature, deformation degree and strain rate to investigate the performance of Monel K-500 alloy in hot working process. The research results show that moderate temperature, higher strain rate and deformation degree will be favorable to improve crystal structure and mechanical property of Monel K-500 Alloy.

Study on the Microstructures and Properties of the Lead-Free Easy-Cutting Bial-Brass

Traditional lead brass products pollute the environment and do harm to the human health. Fabrication of the new kind of the brass without lead is an urgent task. Bi-brass is the most popular lead-free easy-cutting brass. However, its mechanical and hot-working properties are not satisfied. In present paper, aluminum element was added into the Bi-brass alloy in order to improve the alloy’s mechanical and hot-working property. Experiment results showed that the aluminum can increase the surface tension of the Bi and change the existing morphology of Bi from film-like into particle-like. Therefore, the ingot’s hot-working property is excellent. Experiment results showed that even the extrusion ration reaches 256, the ingot still can be extruded into rod successfully. Experiment results also indicated that the homogenizing annealing treatment on the ingot and addition of the rare earth La did not improve the mechanical properties or the machinability.

Analysis of Factors Influencing Spatial Stiffness of Cable-Strut-Supported Rigid Shell Structure

Long-span hybrid structures have been widely used in recent years. Composition and working mechanism of cable-strut-supported rigid shell structure of a gymnasium roof are analyzed in this paper. Influences of different type of supports and bracing members on the spatial working property of this hybrid structure and factors that influence stiffness of the structure are analyzed too. Analysis results identify the formation mechanism of spatial stiffness of the hybrid structure. The research results can shed light on study and designing of the same kind of structure.

Investigation of Experimental Model for Designing Concrete Bridge Deck Reinforced with GFRP Bars

Since the traditional design methods are based on the simply-supported experimental model, the bearing capacity of concrete bridge deck reinforced with GFRP bars is often determined by serviceability limits. The predicted bearing capacity is so low that high reinforcement ratio and construction cost are lead to. However, the previous researches on concrete bridge decks reinforced with GFRP bars revealed that crack widths and deflections were far less than the predictions by traditional codes, due to the existing of compression membrane action. This paper proposes a restraint test model to stimulate the comprehensive working property of deck system，considering the restraint from other part of the deck. Compared with simply-supported test model, bearing capacity and serviceability of the proposed are improved by more than 1 time. New experimental model for designing concrete bridge deck reinforced with GFRP bars are required.

Study on the Lead-Free Easy-Cutting Mg-Sb Brass

Traditional lead brass is gradually prevented from application by many countries’ governments because lead does harm to human health and pollutes the environment. New types of environment-friendly lead-free brass with favorable machinability are urgently demanded in the electrical, electronics and plumping fields. Lead-free Mg-Sb brass was fabricated in present. Experimental results showed that when the content of Mg is 1.0wt%, Sb is 0.8wt% and Cu is 58.0~59.0wt%, the alloy’s mechanical properties and machinability are favorable for industry application. With the increase of the content of Sb, the machinability increased, while the mechanical properties decreased. Lots of Cu2Mg and Cu9Sb2 particles on the order of microns exist in the inner-grain and grain boundaries. These particles improve the machinability, however, lower the tensile strength and the elongation. A three-way pipe joint was successfully punched with the fabricated Mg-Sb brass bar, and this demonstrated that the fabricated Mg-Sb brass possesses favorable hot working property.

Analysis of Spatial Co-Working Property of a Long-Span Cantilevered Awning

A chamfering rectangular long-span stadium awning is introduced in this paper. To fully understand the spatial co-working property of the cantilevered structure, the function of connecting members in this cantilevered structure is studied. Analysis results identified the formation mechanism of spatial stiffness of the whole cantilevered structure. The research results can shed light on structural study and designing of the same kind.