Coating process optimization through in-line monitoring for coating weight gain using Raman spectroscopy and design of experiments

Silicon microwires (MWs) previously synthesized using the VLS method with gold catalyst are being carburized at 1100°C under methane aiming to their conversion to SiC. SEM, TEM as well as XPS and Raman spectroscopy were used for structural and morphological characterization. After carburization achievement, SiC is found to be polycrystalline with a high density of stacking faults associated to an increase of surface roughness. Directions for the carburization process optimization are given.

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On the Hardfacing Performance Optimization after Plasma Transfer Arc Experiments

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.3640 ◽

2011 ◽

Vol 189-193 ◽

pp. 3640-3646

Author(s):

Ming Der Jean ◽

Ming Cheng Li ◽

Tzu Hsuan Chien ◽

Ching Jyi Chen

Keyword(s):

Design Of Experiments ◽

Response Surface ◽

Performance Optimization ◽

Three Dimensional ◽

Surface Hardness ◽

Statistical Design ◽

Yield Enhancement ◽

Coating Process ◽

Hardness Model ◽

Coating Design

The paper describes response surface methodology (RSM) based on design of experiments and analysis of variance (ANOVA) as a statistical design while developing a robust plasma transfer arc (PTA)coating process. Based on ANOVA, The relative important parameters with respect to surface at hardness values were identified in the Taguchi design, where they were further used in predictors. In addition, we applied three-dimensional graphs in RSM to develop a robust PTA response surface yielding the desired-better area of a treated layer. In this study, a quadratic polynomial with a Box-Behnken design is utilized. The results reveal that RSM provides the effective methods as compared to the traditional trial-and-error method for exploring the effects of controlled factors on response. A very good agreement was observed, as evidenced by R-squared value, 90%, between the predicted and the experimental data, and its error percent is found to be approximately 3.801% in the PTA-coating process. It is clear that RSM model demonstrated better accuracy in predicting surface hardness for PTA-coating process. Accordingly, RSM based on design of experiments was used as statistical PTA-coating design tools combined with the hardness model. Device zone optimization and yield enhancement have been demonstrated.

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Coating Binder Migration and Affected Parameters: Influence of Coating Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.791-793.187 ◽

2013 ◽

Vol 791-793 ◽

pp. 187-191

Author(s):

Zhao Hui Zhen ◽

Zheng Shun Wang

Keyword(s):

Cross Section ◽

Dwell Time ◽

Coating Layer ◽

Drying Rate ◽

Coating Process ◽

Coated Paper ◽

Drying Temperature ◽

Coating Surface ◽

Binder Concentration ◽

Coating Weight

The coating binder in cross-section of coating layer will be migrated, the binder concentration will be different in z-direction of coating layer, which affect some properties of coated paper. The paper studied the effects of coating progress on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. During coating process the drying rate, dwell time from coating device to dryer and coating weight affect the binder migration. The mechanism of binder migration was proposed. The results indicated that the degree of binder migration is directly proportional to the drying temperature and coating weight, but reduces with extending the dwell time.

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