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Purpose The effects of infiltrant-related factors during post-processing on mechanical performance are fully considered for three-dimensional printing (3DP) technology. The factors contain infiltrant type, infiltrating means, infiltrating frequency and time interval of infiltrating. Design/methodology/approach A series of printing experiments are conducted and the parts are processed with different conditions by considering the above mentioned four parameters. Then the mechanical performances of the parts are tested from both macroscopic and microscopic papers. In the macroscopic view, the compressive strength of each printed part is measured by the materials testing machine – Instron 3367. In the microscopic view, scanning electron microscope and energy dispersion spectrum are used to obtain microstructure images and element content results. The pore size distributions of the parts are measured further to illustrate that if the particles are bound tightly by infiltrant. Then, partial least square (PLS) is used to conduct the analysis of the influencing factors, which can solve the small-sample problem well. The regression analysis and the influencing degree of each factor are explored further. Findings The experimental results show that commercial infiltrant has an outstanding performance than other super glues. The infiltrating action will own higher compressive strength than the brushing action. The higher infiltrating frequency and inconsistent infiltrating time interval will contribute to better mechanical performance. The PLS analysis shows that the most important factor is the infiltrating method. When compare the fitted value with the actual value, it is clear that when the compressive strength is higher, the fitting error will be smaller. Practical implications The research will have extensive applicability and practical significance for powder-based additive manufacturing. Originality/value The impact of the infiltrating-related post-processing on the performance of 3DP technology is easy to be ignored, which is fully taken into consideration in this paper. Both macroscopic and microscopic methods are conducted to explore, which can better explain the mechanical performance of the parts. Furthermore, as a small-sample method, PLS is used for influencing factors analysis. The variable importance in the projection index can explain the influencing degree of each parameter.

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The surface properties and cavitation erosion performance of NiTi/NiCr-75%Cr3C2 composite coatings on AISI 304 stainless steel substance by atmospheric plasma spraying (APS) at different hydrogen gas flow rate were investigated. Composite coatings were characterized for microhardness. Microstructure of the cross section of composite coatings were investigated by scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS). Caivation erosion test was finished by ultrasonic stretching vibration caviation test machine. The results show that when the hydrogen gas flow rate is 3L/min and 6L/min, the microhardness of coatings are respectively 640 HV and 730 HV at a load of 100 g and a dwell time of 15s condition, and the composite coatings by APS generates porosity and were oxidized. The cavitation erosion resistance of composite coatings is better than that of nodular cast iron. As the hydrogen gas flow rate increases, the microstructure of composite coating deposited by APS has lower porosity, and the better cavitation erosion resistance.