Solid State Phenomena Vol. 330

Abstract: The purpose of this research was to study the diffuse element and mechanical property of Semi-solid casting (SSC) 7075 and 6061 Al alloy from diffusion welding (DW). The results found that Zn elements were successfully diffused. Mg₂Si and MgZn₂ intermetallics were precipitated from plate-like shape to flake shape. The high bonding temperature and bonding time caused diffuse elements distributed throughout the material. The mechanical property showed that the maximium average tensile strength was 76.80 MPa from bonding temperature at 723 K and 120 min bonding time. The hardness in bonded line was around 63 HV to74 HV.

Abstract: Single point incremental forming (SPIF) process is used to deform complex shapes. Through SPIF process metallic sheet is formed. The formability of a AA5052 is evaluated using SPIF method for industry level product. The utility of SPIF is broad in industries because of the simple operating system of manufacturing and designing metal substances throughout computer design combined with the CNC machine. While forming Mantellic sheet there are many benefits. This process is extensively adopted in automobile, aeronautical, and medical industries for engineering complex parts. In this paper, the main objective is to examine the formability of AA5052 aluminum alloy raw material with various wall angles and operating boundaries using the modified computer numerical control (CNC) milling machine. Here, the shape correctness and the surface roughness are focused for computing the forming depth, wall angle, and spring-back for obtaining improved parts with a proper material with finish surface. For verifying the real-time experiments and evaluating the existence of stress, strain, and thickness variations.

Abstract: Polybutylene succinate (PBS) with bentonite was investigated for its rheological, thermal and water absorption properties. The bentonite (BTN) was modified with soybean oil (SBO) and lard oil (LO) (2:98 clay: oil % by weight) by mechanical stirring and ultrasonication. The composites were prepared using an internal mixer and processed by compression molding. Under the bentonite modification conditions, XRD showed that the bentonite layers were penetrated with edible oils into the small layers and the enhancement of d-spacing between the BTN-layers in the composites. A small platelet-like structure of the modified bentonite composites was observed by SEM micrographs. The increase in MFI of untreated bentonite displayed the viscosity of PBS involving the moisture and water molecules decreased the frictional force. In addition, the viscosity of composites between PBS and treated bentonite with LO represented in an increase of the MFI value. Regarding the thermal properties, the presence of bentonite could act as a nucleating agent for PBS at low content (1-2%). Moreover, the treated with edible oils of bentonite could increase the percentage crystallinity of PBS at higher bentonite content. The presence of bentonite tends to increase the water absorption behavior of PBS/bentonite composites.

Abstract: Al₂O_3f/SiO₂ and SiO_2f/SiO₂ ceramic matrix composites were manufactured by silica sol-infiltration-sintering method. The mechanical properties of composites under room temperature to 1200 °C were tested on-line with universal testing machine. It is found that Al₂O_3f/SiO₂ composites present a higher strength than SiO_2f/SiO₂ at room temperature and 1000 °C. The strength of two composites dramatic decrease with temperature increased to 1200 °C. Also, SEM and XRD methods were adopted to investigate the micro-structure of cross-fraction and crystal phase of composites, indicating a strong interaction between fibers and matrix under high temperature. Finally, the dielectric properties of two composites under room temperature to 1200 °C were discussed.

Abstract: A new type of no-demolition insulation formwork was designed with EPS foam concrete as the frost and fire resistant protection layer and polystyrene board as the insulation layer. Tests were conducted on foam concrete to analyze the flexural performance and safety of the formwork. The results show that EPS foam concrete has excellent performance, and when EPS foam concrete with density grade A08 is used as the protective layer, the mechanical properties of the formwork meet the requirements of "Thermalinsulation free from demolition template for buildings" JC/T 2493-2018, which provides a reference basis for its application in the construction field.

Abstract: Ceramsite was prepared from sludge, oil sludge and building residue, and the ratio of ceramsite and sintering process was determined by orthogonal test. The effects of different ratios and sintering process on the compressive strength and bulk density of ceramsite were studied. The strength and thermal conductivity of ceramsite foam concrete were tested by using prepared ceramsite as light aggregate to determine the optimal ratio scheme of ceramsite foam concrete. By designing the early cracking test of concrete, the cracking inhibition effect of ceramsite in foam concrete was explored, which provided a theoretical basis for the application of foam concrete.

Abstract: At present, fiber reinforce plastic (FRP) sucker rod has the advantages of high tensile strength, light weight and strong corrosion resistance which gradually applied and popularized in offshore oil and gas field. However, the bonded joint of FRP sucker rod is particularly prone to break and fall off. Current research works mainly focus on the mechanical properties of FRP sucker rod and less consideration was given to adhesive performance. This paper proposed a finite element model (FEM) of bonded joint. The maximum predicted load of bonded joint was acquired and the axial distribution of adhesion stress and slip distance in the bonding interface was studied, which can provide theoretical basic of bonded joint and extend the service life of downhole pumping operation.

Abstract: Objective: To study the fracture resistance and failure modes of different type of ceramic crowns. Methods: Four groups of crown including zirconia-veneering porcelain crown (Group 1), whole zirconia crown (CAD/CAM, Group 2), cast ceramic crown (Group 3) and glass ceramic crown (CAD/CAM, chairside, Group 4) with the same thickness were manufactured, each group own 12 crowns. The fracture resistance test and failure modes analysis of the specimens were conducted, SPSS22.0 was used to analyze the difference among the groups. Results: The fracture strength of Group 2 is significantly higher than other three group (P<0.05), Statistical significance was found between group 3 and group 1, group 4. No Statistical significance was found between group 1 and group 4. The failure modes of the whole zirconia crown, the cast ceramic crown and the glass ceramic crown are complete crown fracture; 33% of the zirconia-veneering porcelain crown showed veneering layer fracture, the other 67% showed complete crown fracture. Conclusion: The fracture resistance of the whole zirconia crown are higher than the cast ceramic crown, the zirconia-veneering crown and the glass ceramic crown and the glass ceramic crown (CAD/CAM) is a very convenient prostheses. The failure modes are significantly influenced by the type of the crown.

Abstract: In this research, vibrations were added to the mold structure. In the molding process, each vibration was turned on during the filling process. Moreover, the mold structure was re-designed to insert the vibration equipment. The design of this equipment is an early version used to insert vibrations. This option was chosen to facilitate the process of manufacturing and installing the vibration part. However, the applied method still has some limitations, such as not exerting an impact on the exact position where the weld line occurs. To overcome this disadvantage and to help increase the vibrations of the insert, we used a flexure hinge placed inside the insert. This design helped to improve the flow disturbance and to accurately impact the position where the weld line occurred. Therefore, the results of our method are better than those of the method currently being applied.

Abstract: The Li₄Ti₅O₁₂/Co₃O₄ composites were prepared by hydrothermal reaction method with different Co₃O₄ mass content (3%, 7%, 11%, and 15%). The Li₄Ti₅O₁₂ nanoparticles were set in-situ on the Co₃O₄ sheet. Co ion was doped into the Li₄Ti₅O₁₂ lattice. The first cycle specific capacity firstly increased and then decreased with Co₃O₄ content increasing, which the discharge capacity reached the peaking value that the first capacity was 1111 mAh/g and the specific discharge capacity retained 240 mAh/g after 200 cycles. After 200 cycles of charge and discharge, the retention of the capacity was 96.4% at 0.1 A/g, and the retention of the capacity was 98.4% at 0.5 A/g.