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The purpose of this study is to develop a practical method for training students how to conduct statistical analysis and do a course project in design of experiments (DOEs) course through the Web-based virtual catapult simulation.

A step-by-step sequential DOE process for investigating the effects of controllable factors on quality characteristic responses was presented as a guideline for conducting a DOE course project. Each team was assigned to create an innovative teaching material and work on the term report by following the recommended guidelines for designing experiments through the Web-based virtual catapult simulation. Hypothesis was defined to test whether doing a course project based on this approach would impact students’ learning outcome.

The Web-based virtual material was an alternative technique for interactive teaching that could improve students’ understanding and achievement in DOE course projects. There was a significant difference in student learning and understanding before and after doing on the course project through the Web-based virtual catapult simulation. The students had improved communication and teamwork skills after following the recommended procedure for practicing DOEs.

Most students could effectively conduct designing experiments, carry out designed experiments, analyze data and gain valuable teamwork experience. After learning the DOE approach based on the catapult simulation, they enjoyed working on their course projects deploying to the innovative toys and other real-life situations with real measurements.

The use of Web-based virtual material, including catapult simulation, was an alternative technique for interactive DOE teaching to improve the students’ understanding and achievement in DOE course projects.

This paper aims to compare the wear behavior, surface roughness, friction coefficient and volume loss of high-velocity oxy-fuel (HVOF) sprayed WC–Co and WC–Cr₃C₂–Ni coatings on AISI 1095 steel with spraying times of 10 and 15 s.

In this study, the pin-on-disc testing technique was used to evaluate the wear characteristics at a speed of 0.24 m/s, load of 40 N and test time of 60 min under dry conditions at room temperature. The wear characteristics were examined and analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy. The surface roughness of a coated surface was measured, and microhardness measurements were performed on the cross-sectioned and polished surfaces of the coating.

Spraying time and powder material affected the hardness of HVOF coatings due to differences in the porosity of the coated layers. The average hardness of the WC–Cr₃C₂–Ni coating with a spaying time of 15 s was approximately 14% higher than that of the WC–Cr₃C₂–Ni coating with a spraying time of 10 s. Under an applied load of 40 N, the WC–Co coating with a spraying time of 15 s had the lowest variation in the friction coefficient compared with the other coatings. The WC–Co coating with a spraying time of 10 s had the lowest average and variation in volume loss compared to the other coatings. The WC–Cr₃C₂–Ni coating with a spraying time of 10 s exhibited the highest average volume loss. The wear features changed slightly with the spraying time owing to variations in the hardness and friction coefficient.

This study investigated tribological performance of WC–Co; WC-Cr₃C₂-Ni coatings with spraying times of 10 and 15 s using pin-on-disc tribometer by rotating the relatively soft pin (C45 steel) against hard coated substrate (disc).