Shape-programmable soft materials that exhibit integrated multifunctional shape manipulations, including reprogrammable, untethered, fast, and reversible shape transformation and locking, are highly desirable for a plethora of applications, including soft robotics, morphing structures, and biomedical devices.Despite recent progress, it remains challenging to achieve multiple shape manipulations in one material system. Here, we report a novel magnetic shape memory polymer composite to achieve this. The composite consists of two types of magnetic particles in an amorphous shape memory polymer matrix. The matrix softens via magnetic inductive heating of low-coercivity particles, and highremanence particles with reprogrammable magnetization profiles drive the rapid and reversible shape change under actuation magnetic fields. Once cooled, the actuated shape can be locked. Additionally, varying the particle loadings for heating enables sequential actuation. The integrated multifunctional shape manipulations are further exploited for applications including soft magnetic grippers with large grabbing force, sequential logic for computing, and reconfigurable antennas.

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Functional parts require high a level of strength and the current Fused Deposition Modelling (FDM) cannot be fully utilized as the end used parts. The poor mechanical strength is caused by the incomplete layer bonding during the printing process. In the printing process, the interlayer bonding is made too quick thus the layers are not fully fused together causing the reduced tensile strength. This paper presents a possible solution to this problem by incorporating vacuum technology in FDM system to improve tensile strength of 3D printed specimens. In this study, a desktop FDM machine was placed and operated inside a low pressure vacuum chamber. The results obtained show an improvement of 12.83 % of tensile strength compared to the standard specimen. This paper concludes that the low pressure environment is useful in reducing the heat loss due to convection of air, hence directly improves the specimen's tensile strength.