Implantation fuer tribologische Anwendungen Oberflaechen- und Phasenanalyse stickstoff- und borimplantierter Staehle zur Verfahrensoptimierung. Abschlussbericht

Empirical results on the strength enhancement of steels by N- and B-implantation should be explained from a materials science point of view. The methods applied were X-ray diffractometry and element depth profiling. The investigations of N-implanted steels focussed on the nitride formation in selected model materials and, with respect to applications, in: X90 CrMoV and S 6-5-2 tool steels, austenite X10 CrNiTi189 as well as in hard chromium plates. Main topic in B-implanted steels were the transformations: crystalline Fe-phase - amorphous Fe-B-phase - crystalline boride phases. The result is an improvement in process control by first an insight into the strength enhancing mechanisms and second in into their generation depending on the materials microstructure and the process parameter. (orig.)Empirische Ergebnisse zur Festigkeitssteigerung von Staehlen durch N- und B-Implantation sollten werkstoffphysikalisch begruendet werden. Aufgabe war die Untersuchung mit Roentgendiffraktometrie und Element- Tiefenprofilierung. Schwerpunkt bei N-Implantation war die Nitridbildung in Modellmaterialien und -anwendungsbezogen- in: X90 CrMoV18 und S 6-5-2, im Austenit X10/CrNiTi 189 sowie in Hartchromschichten. Schwerpunkt bei Borimplantation war die Umwandlung: Kristalline Fe-Phase - amorphe Fe-B-Phase - kristalline boridphase und deren Quantifizierung. Ergebnis: Verbesserte Prozessfuehrung durch das Verstaendnis der festigkeitssteigernden Mechanismen und ihrer Erzeugung in Abhaengigkeit vom Werkstoff und den Verfahrensparametern. (orig.)SIGLEAvailable from TIB Hannover: F93B488+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Repurposing CPAP machines as stripped-down ventilators

Abstract The worldwide shortage of medical-grade ventilators is a well-known issue, that has become one of the central topics during the COVID-19 pandemic. Given that these machines are expensive and have long lead times, one approach is to vacate them for patients in critical conditions while patients with mild to moderate symptoms are treated with stripped-down ventilators. We propose a mass-producible solution that can create such ventilators with minimum effort. The central part is a module that can be attached to CPAP machines and repurpose them as low-pressure ventilators. Here, we describe the concept and first measurements which underline the potential of our solution. Our approach may serve as a starting point for open-access ventilator technologies