Topic: NASA Engineering and Safety Center

Topic

TB 26-10 Printed Circuit Board Assembly Chip Resistor Body Cracking

For more information, contact Joel W. Sills, Langley Research Center, joel.w.sills@nasa.gov. Download PDF here Chip resistors are widely used in NASA projects, yet cases of alumina substrate cracking during environmental testing are rare. Two instances of thick-film chip resistor cracking were observed during thermal cycling after vibration, with fractures occurring across the short axis due […]

3 Nov 2026, 16:32 UTC

Science

TB 26-09 Measured Hammer-Tap Inputs

For more information, contact Joel W. Sills, Langley Research Center, joel.w.sills@nasa.gov. Download the PDF version An instrumented hammer test does not require an idealized single half-sine waveform. When the complete force and response are measured accurately, crest ripples and separated contacts remain known inputs. Force shape changes excitation, but does not inherently invalidate the record. […]

2 Nov 2026, 22:28 UTC