Immersion Ultrasonic Testing of Artificially Induced Defects in Fused Filament Fabricated Steel 316L.

Fused filament fabrication (FFF) with the use of metal-polymer filaments offers a cost-effective solution in additively manufacturing metal parts. Nevertheless, the quality and dimensional characteristics of the FFF produced parts needs to be assured. This short communication reports results and findings from an ongoing investigation on the use of immersion ultrasonic testing (IUT) for the detection of defects in FFF metal parts. In this work, the BASF Ultrafuse 316L material was used with an FFF 3D printer to produce a test specimen for IUT inspection. Two types of artificially induced defects were examined: drilling holes and machining defects. The obtained inspection results are promising in terms of the capability of the IUT method to detect and measure the defects. It was found that the quality of obtained IUT images is not only probe frequency dependent but also sensitive to the part characteristics, indicating a need for a wider range of frequencies and more accurate calibration of the system for this material.

The Balance Between Safety and Productivity and its Relationship with Human Factors and Safety Awareness and Communication in Aircraft Manufacturing.

BACKGROUND: This paper presents the findings of a pilot research survey which assessed the degree of balance between safety and productivity, and its relationship with awareness and communication of human factors and safety rules in the aircraft manufacturing environment. METHODS: The study was carried out at two Australian aircraft manufacturing facilities where a Likert-scale questionnaire was administered to a representative sample. The research instrument included topics relevant to the safety and human factors training provided to the target workforce. The answers were processed in overall, and against demographic characteristics of the sample population. RESULTS: The workers were sufficiently aware of how human factors and safety rules influence their performance and acknowledged that supervisors had adequately communicated such topics. Safety and productivity seemed equally balanced across the sample. A preference for the former over the latter was associated with a higher awareness about human factors and safety rules, but not linked with safety communication. The size of the facility and the length and type of employment were occasionally correlated with responses to some communication and human factors topics and the equilibrium between productivity and safety. CONCLUSION: Although human factors training had been provided and sufficient bidirectional communication was present across the sample, it seems that quality and complexity factors might have influenced the effects of those safety related practices on the safety-productivity balance for specific parts of the population studied. Customization of safety training and communication to specific characteristics of employees may be necessary to achieve the desired outcomes.