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Realizing the full potential of advanced fiber reinforced polymeric composites has been impeded by their weak interlaminar performance. Herein, a wholethrough-thickness stitching strategy was proposed to address this key challenge by using ultrathin, high performance aligned carbon nanotube (CNT) composite belts as stitching sutures. During the fabrication of aligned CNT composite belts, the as-made CNT belts that consist of randomly orientated CNTs were firstly stretched before resin infiltration. It has been found that the tensile strength and modulus of aligned CNT composite belts reached 1126.9 MPa and 56.2 GPa, with an improvement of 227.9% and 726.5% than those of unstretched composite belts, respectively. After stitching, the Mode I interlaminar fracture toughness and through-thickness electrical conductivity of carbon fiber reinforced laminated composites was enhanced by 138.7% and 426.7%, respectively, which was mainly due to the bridging effect of strong and conducting CNT belts. In addition, the interlaminar crack propagations can be in situ monitored by tracking the resistance variation of the stitched laminates under loading. Thus, this stitching strategy provides an effective approach to not only enhance the structural performance of fiber reinforced polymeric composites, but also enrich their functionalities.

This paper used aluminum-alloy-2A02 (paramagnetic) and High-Speed-Steel (HSS) W18Cr4V (ferromagnetic) as the research objects to study the effect of DC magnetic-field on the dry tribology performance adopting the mutual matching methods (aluminum-alloy pin to HSS ring and HSS pin to aluminum-alloy to HSS ring, respectively). The wear rate of aluminum-alloy ring coupled with HSS pin was larger than that of pin coupled with HSS ring, which indicated that the influence of contacted surface size and hardness of friction pairs should be considered in the tribological research and application. The material of high magnetic permeability led to the wear rate decreases under a magnetic-field. The mechanism of sliding wear namely the ferromagnetic debris is adsorbed by HSS surface under the magnetic force. The wear rate is affected by the magnetic force depending on pin/disc material in a magnetic-field. The friction coefficient of aluminum-alloy pin/HSS ring is larger than that of HSS pin/aluminum-alloy ring, indicating the high difference of magnetic permeability for the coupled materials is disadvantageous to the antifriction effect of magnetic-field.

Wr'lte Pub.l'lcations Manager SPE P 0 Box 833836, Richardson, TX 75083-3836. Telex, 730989 SPEDAL. where and by w om t e paper 1s pres en . , , · · _ ABSTRACTIn this paper we present a model for calculating water saturations in clean, fine-grained, fractured rocks.The model, called the fracture/matrix (F/M) model, is used to calculate a composite poro~ity exponent, m, which is then used in Arch1e's relationship to calculate water saturations.An application of the F/~ model.to wells located in S.E. New Mex1co wh1ch penetrate the Bone s·pring sands is presented.

Wr'lte Pub.l'lcations Manager SPE P 0 Box 833836, Richardson, TX 75083-3836. Telex, 730989 SPEDAL. where and by w om t e paper 1s pres en . , , · · _ ABSTRACTIn this paper we present a model for calculating water saturations in clean, fine-grained, fractured rocks.The model, called the fracture/matrix (F/M) model, is used to calculate a composite poro~ity exponent, m, which is then used in Arch1e's relationship to calculate water saturations.An application of the F/~ model.to wells located in S.E. New Mex1co wh1ch penetrate the Bone s·pring sands is presented.

Nowadays, the level of stamping dies in the world has been greatly improved, and stamping technology has also developed greatly. Based on the analysis of the pallet parts, it is determined that the required processes are punching and blanking. The compound dying for punching and blanking was chosen for processing after the processing method was examined. Specific design process: analyze the material used for the part, calculate the required punching force, and select the required press according to the punching force, the closing height of the die, and the size of the die handle hole. The parts required by the die, such as convex and concave die, stripper plate, fixed plate, and other components, should also be designed so that the processing of the parts can be completed after the assembly is completed. In the design process, CAD drawing software, three-dimensional drawing software, etc., can be used to complete the drawing of two-dimensional and three-dimensional drawings of parts, improve the efficiency of our drawing, and can also quickly solve problems existing in the drawing, which makes the design process simpler.

To suppress numerical instabilities and ensure manufacturability in density-based topology optimization, restrictions are required to be used. In this paper, a new bilateral density filter is presented. Different from the original bilateral density filter, the new filter uses a cross template and the range operator is changed. The purpose is to improve the ability of edge-preserving smoothing. Moreover, a continuation scheme for the new range operator is given to ensure a stable convergence to 0–1 solutions and avoid falling into local minima. The performance of the new filter for compliance minimization problem and compliant mechanism problem is demonstrated by application examples.