This work aims at investigating the effect of thermal aging on tensile properties of three-dimension (3D) and five-direction braided carbon fiber/BMI resin composites prepared by resin transfer molding (RTM) process. The influence of high temperature on the tensile strength and the failure mechanisms of un-aged and aged composites were studied, respectively. As for the thermal aging condition, 180 for 24h was selected. The tensile strength of both un-aged and aged specimens were tested by SHIMADZU universal material testing machine at room temperature. The fracture modes of specimens were observed by scanning electron microscopy (SEM). It was found that the tensile load at break and tensile strength decreased after ageing. From the SEM views of the failed samples, the fracture surface presented hackles which were specific to the debonding of the interface between fibers and matrix. A lot of fibers were pulled-out in the aged state specimen. It can be confirmed that the failure occurred at the fiber/matrix interface and the fiber/matrix interface seemed to be weak in aged carbon fabrics reinforced BMI composites.

In order to investigate the effect of splicing shape and splicing interval length of reinforced fabric on the mechanical performance for manufacturing composite parts in complicated shape with laminated 2D glass fiber woven fabric. On the basis of [0º/45º/90º/90º/0º] S ply sequence, six kinds of laminated performs with different splicing interval lengths which were 4mm, 8mm, 12mm respectively and two different splicing shape which were ladder splicing (LS) and double vertical line splicing (DLS), and a kind of laminated perform with continuous laminates (CL) of 2D glass fiber woven fabric were made. By means of RTM molding technology, the technological parameters of RTM processing were designed as follows: injection temperature was 25°C, injection duration time was 180min and injection pressure was 0.4MPa, the epoxy resin based 2D glass fiber woven fabric RTM laminated specimen were prepared. According to the GB/T 1447-2005 and GB/T 1449-2005standard test method, the tensile and flexural properties of the 2D glass fiber woven fabric laminated RTM specimen were tested. It was found that the tensile fracture position were all near the splicing line, the main reason of which was the concentration of tensile stress. The tensile and flexural test results show that the difference of the splicing shape and the splicing interval length will generate a significant effect on the mechanical performance of the laminate. All above experimental results could provide fundamental data to the optimal design complex structure laminated composite parts.

This paper presents an experimental investigation on the failure modes of glass fiber reinforced 2D woven fabric with ladder splicing laminate composites. On the basis of [0/0/+45/90/-45/90]s ply sequence, six kinds of laminated performs with different splicing interval lengths which were 4mm, 8mm, 12mm respectively and two different splicing shape which were ladder splicing and double vertical line splicing, and a kind of laminated perform with continuous laminates of 2D glass fiber woven fabric were made. By means of RTM molding technology, the technological parameters of RTM processing were designed as follows: injection temperature was 25°C, injection duration time was 180min and injection pressure was 0.4MPa, the epoxy resin based 2D glass fiber woven fabric RTM laminated specimen were prepared. According to the GB/T 1447-2005 and GB/T 1449-2005standard test method, the failure modes of 2D glass fiber woven fabric laminated RTM specimen were tested. Results show that the failure modes of laminate composites manifest as rapid damage in the form of line inlay mode and wedge shape mode at 4mm interval length condition, and accumulating failure in the form of inlay layer slippage - fiber pulled out mode and fiber fracture - splicing layer deboning mode at 12mm interval length. Otherwise, all fracture position of splicing laminates occurs at the site of splicing line because of the concentration of tensile stress.

With copper and copper alloys widely used, copper corrosion has already caused huge economic losses. Super-hydrophobic surface treatment, a new kind of corrosion resistant technology, can effectively inhibit metal corrosion. This paper introduces the basic issues and the construction methods of copper and copper alloys super-hydrophobic surface. The effect of super-hydrophobic surface on the corrosion performance of copper and copper alloys is analyzed emphatically. Recent developments of super-hydrophobic surface and the existed technical barriers are also summarized in the paper.

This research paper presents an experimental investigation on the compression and compressive resilience properties of warp-knitted spacer fabric composites with different resin content and different kinds of resin. By means of hand roller coating technology, four kinds of warp-knitted spacer fabric composites were made. The experiments were tested according to GB/T1453-2005 and ISO3386/2:1984. It is shown that the resin content and resin type seriously affect the compression and compressive resilience properties of warp-knitted spacer fabric composite. The data indicated that when the warp-knitted spacer fabric composite coated with the same kind of resin, with increasing resin content the elastic modulus added and the compressive resilience decreased. Having the same resin content, the compression properties of pacer fabric composite increase with the increase of flexural strength of resin; while the compressive resilience decrease.