Lean Thinking Simulation Model to Improve the Service Performance in Fast Food

The titanium alloy blade is a key part of an aero-engine, but its high surface efficiency and precision machining present technical problems. Belt grinding can effectively prolong the fatigue life of the blade and enhance the service performance of the aero-engine. However, the residual stress of the workpiece after belt grinding directly affects its service performance and life. The traditional single particle abrasive model simulation is limited in exploring the influence of grinding process parameters on surface residual stress. In this study, an ABAQUS simulation model of multi-particle belt grinding is established for titanium alloy material, a finite element (FE) simulation is conducted with different technological parameters, and the results are analysed. The critical belt grinding experiment is conducted on thin-walled titanium alloy parts, and the distribution characteristics of surface residual stress after grinding are studied to understand the influence of grinding parameters on the formation of surface residual stress. Comparing the results of the FE simulation and the grinding experiment, the common law of stress change and the prediction model are obtained. The results show that the multi-particle belt grinding simulation is consistent with the belt grinding experiment in terms of the influence of grinding parameters on residual stress. The simulation can serve as a guide in actual belt grinding to some extent. Directions for improving the multi-particle abrasive simulation model are discussed.

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Light-cured dental composites characterization by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175272 ◽

1990 ◽

Vol 48 (4) ◽

pp. 428-429

Author(s):

B. M. Culbertson ◽

M. L. Devinev ◽

E. C. Kao

Keyword(s):

Electron Microscopy ◽

Mechanical Analysis ◽

Service Performance ◽

Dental Composite ◽

Dental Composites ◽

Neat Resin ◽

Scanning Calorimetry ◽

Research Meeting ◽

Formulation Variables

The service performance of current dental composite materials, such as anterior and posterior restoratives and/or veneer cements, needs to be improved. As part of a comprehensive effort to find ways to improve such materials, we have launched a broad spectrum study of the physicochemical and mechanical properties of photopolymerizable or visible light cured (VLC) dental composites. The commercially available VLC materials being studied are shown in Table 1. A generic or neat resin VLC system is also being characterized by SEM and TEM, to more fully understand formulation variables and their effects on properties.At a recent dental research meeting, we reported on the differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) characterization of the materials in Table 1. It was shown by DSC and DMA that the materials are substantially undercured by commonly used VLC techniques. Post curing in an oral cavity or a dry environment at 37 to 50°C for 7 or more hours substantially enhances the cure of the materials.

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