Induction Consolidation of Thermoplastic Composites Using Smart Susceptors

This project has focused on the area of energy efficient consolidation and molding of fiber reinforced thermoplastic composite components as an energy efficient alternative to the conventional processing methods such as autoclave processing. The expanding application of composite materials in wind energy, automotive, and aerospace provides an attractive energy efficiency target for process development. The intent is to have this efficient processing along with the recyclable thermoplastic materials ready for large scale application before these high production volume levels are reached. Therefore, the process can be implemented in a timely manner to realize the maximum economic, energy, and environmental efficiencies. Under this project an increased understanding of the use of induction heating with smart susceptors applied to consolidation of thermoplastic has been achieved. This was done by the establishment of processing equipment and tooling and the subsequent demonstration of this fabrication technology by consolidating/molding of entry level components for each of the participating industrial segments, wind energy, aerospace, and automotive. This understanding adds to the nation's capability to affordably manufacture high quality lightweight high performance components from advanced recyclable composite materials in a lean and energy efficient manner. The use of induction heating with smart susceptors is a precisely controlled low energy method for the consolidation and molding of thermoplastic composites. The smart susceptor provides intrinsic thermal control based on the interaction with the magnetic field from the induction coil thereby producing highly repeatable processing. The low energy usage is enabled by the fact that only the smart susceptor surface of the tool is heated, not the entire tool. Therefore much less mass is heated resulting in significantly less required energy to consolidate/mold the desired composite components. This energy efficiency results in potential energy savings of {approx}75% as compared to autoclave processing in aerospace, {approx}63% as compared to compression molding in automotive, and {approx}42% energy savings as compared to convectively heated tools in wind energy. The ability to make parts in a rapid and controlled manner provides significant economic advantages for each of the industrial segments. These attributes were demonstrated during the processing of the demonstration components on this project

Domain structure retrieval of a simulated ferroelectric film via 3D Bragg ptychography

International audienc

Effect of posterior offset humeral components on range of motion in reverse shoulder arthroplasty

The purpose of this study was to evaluate the effect of eccentric humeral components with different degrees of posterior offset on range of glenohumeral motion in reverse shoulder arthroplasty. Uncemented PROMOS® reverse shoulder prostheses were implanted in eight human cadaveric shoulder specimens. Passive range of motion was evaluated with a robot-assisted shoulder simulator. Three movements were tested: abduction, anterior elevation and external rotation. Each specimen was tested with a customary reverse humeral component and two eccentric components with 3 and 6 mm of posterior offset respectively. Mean abduction was 81° (standard deviation [SD] 12) for the customary reverse components, 81° (SD 13) for the 3 mm eccentric and 82° (SD 15) for 6-mm eccentric implants. Mean anterior elevation was 68° (SD 13) in the regular group and 66° (SD 14) and 63° (SD 14) for 3- and 6-mm eccentric groups. With all configurations, 90° of external rotation were achieved without requiring more than 2 N·m of applied rotational moment. Although there was no statistically significant difference between the conventional and the eccentric implants, anterior elevation was decreased by almost 20° in three of eight shoulders with the posterior offset configurations. This was due to a conflict between the proximal humerus and the anterior aspect of the acromion or the coracoid. Although eccentric humeral components can be useful in reverse shoulder arthroplasty to avoid anterior cortical defects in individuals with pronounced humeral head posterior offset, a potential conflict between proximal humerus and scapula may have an unfavourable effect on range of anterior elevation. However, this observation is only true for the uncemented PROMOS® reverse prosthesis. Other reverse shoulder designs with posterior offset components are yet to be tested