The Influence of Impurities in Feed Ingots on the Quality of Castings Made from Nickel Superalloy IN-713C

Abstract The paper presents the results of research on the impact of impurities in the feed ingots (master heat) on the precipitation of impurities in the ATD thermal analysis probe castings. This impurities occur mostly inside shrinkage cavities and in interdendritic space. Additionally, insufficient filtration of liquid alloy during pouring promotes the transfer of impurities into the casting. The technology of melting superalloys in vacuum furnace prevents the removal of slag from the surface of molten metal. Because of that, the effective method of quality assessment of feed ingots in order to evaluate the existence of impurities is needed. The effectiveness of ATD analysis in evaluation of purity of feed ingots was researched. In addition the similarities of non-metallic inclusions in feed ingots and in castings were observed.

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Metallurgical Quality of Feed Ingots and Castings Made from Nickel and Cobalt Superalloys

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.212.215 ◽

2013 ◽

Vol 212 ◽

pp. 215-220

Author(s):

Franciszek Binczyk ◽

Jan Cwajna ◽

Paweł Gradoń ◽

Maria Sozańska ◽

Marek Cieśla

Keyword(s):

Thermal Analysis ◽

Quality Assessment ◽

Shrinkage Cavities ◽

Different Parts

The paper presents the results of ATD thermal analysis of feed ingots (master heat) and castings made from IN-713C, MAR-247 and MAR-509 superalloys. Metallurgical quality assessment was made based on the analysis of dT/dt curve in rage from Teutto Tsol. Furthermore, impurities (oxides of Al, Zr, Hf, Cr etc.) have been identified inside the shrinkage cavities of feed ingots and castings. Significant similarities has been observed between impurities found in ingots, ATD test samples and finished castings. It has been demonstrated that ATD analysis of samples taken from different parts of feed ingot can be effective method of metallurgical quality assessment for these ingots.

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MATERIAL AND THERMAL ANALYSIS OF LASER SINTERTED PRODUCTS

Acta Mechanica et Automatica ◽

10.2478/ama-2013-0003 ◽

2013 ◽

Vol 7 (1) ◽

pp. 15-19 ◽

Cited By ~ 14

Author(s):

Radovan Hudák ◽

Martin Šarik ◽

Róbert Dadej ◽

Jozef Živčák ◽

Daniela Harachová

Keyword(s):

Thermal Analysis ◽

Heat Stress ◽

Thermal Stresses ◽

Processing Parameters ◽

Sintering Process ◽

Input Processing ◽

Thermal Simulations ◽

The Impact ◽

Selection Of

Abstract Thermal analysis of laser processes can be used to predict thermal stresses and consequently deformation in a completed part. Analysis of temperature is also the basic for feedback of laser processing parameters in manufacturing. The quality of laser sintered parts greatly depends on proper selection of the input processing parameters, material properties and support creation. In order to relatively big heat stress in the built part during sintering process, the thermal simulation and thermal analysis, which could help better understand and solve the issue of parts deformations is very important. Main aim of presented work is to prepare input parameters for thermal simulations by the use of RadTherm software (Thermoanalytics Inc., USA), directly during the sintering process and after the process and find out the impact of the heat stress on a final shape and size of the prototype. Subsequently, an annealing process of constructed products after DMLS could be simulated and specified.

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Effect of Mould Components on the Cooling Rate, Microstructure, and Quality of We43 Magnesium Casting Alloy/ Wpływ Zastosowanych Elementów Formy Na Szybkość Chłodzenia, Mikrostrukturę I Jakość Stopu Magnezu We43

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0258 ◽

2014 ◽

Vol 59 (4) ◽

pp. 1527-1532 ◽

Cited By ~ 2

Author(s):

B. Dybowski ◽

A. Kiełbus ◽

R. Jarosz

Keyword(s):

Solid Solution ◽

Shrinkage Porosity ◽

Casting Alloy ◽

Sand Cast ◽

Feeding Method ◽

Magnesium Casting ◽

Metallic Inclusions ◽

The Impact ◽

We43 Magnesium Alloy

Abstract We investigated the impact of the applied cooling and feeding method on the microstructure and metallurgical quality of castings made from WE43 magnesium alloy. Six identical plates with dimensions of 100x50x20 mm were sand cast for use as samples. Each casting was fed and cooled in a different way. The solid solution grain size was evaluated quantitatively using the Met-Ilo software program, and casting defects were observed using a scanning electron microscope Hitachi S3400N. The finest solid solution grain was observed in the castings with only the coolers applied. Non-metallic inclusions were observed in each plate. The smallest shrinkage porosity was observed in the castings with feeders applied.

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Evaluation of Metallurgical Quality of Master Heat IN-713C Nickel Alloy Ingots

Archives of Foundry Engineering ◽

10.2478/v10266-012-0099-5 ◽

2012 ◽

Vol 12 (4) ◽

pp. 5-10 ◽

Cited By ~ 3

Author(s):

F. Binczyk ◽

J. Cwajna ◽

S. Roskosz ◽

P. Gradoń

Keyword(s):

Induction Furnace ◽

Solidification Process ◽

Melting Process ◽

Aircraft Engines ◽

Slag Removal ◽

Metallic Inclusions ◽

Last Stage ◽

Shrinkage Cavities ◽

Heat Ingot

Abstract The paper presents the results of evaluation of the metallurgical quality of master heat ingots and of the identification of non-metallic inclusions (oxides of Al., Zr, Hf, Cr, etc.), which have been found in the shrinkage cavities formed in these ingots. The inclusions penetrate into the liquid alloy, and on pouring of mould are transferred to the casting, especially when the filtering system is not sufficiently effective. The specific nature of the melting process of nickel and cobalt alloys, carried out in vacuum induction furnaces, excludes the possibility of alloy refining and slag removal from the melt surface. Therefore, to improve the quality of castings (parts of aircraft engines), it is so important to evaluate the quality of ingots before charging them into the crucible of an induction furnace. It has been proved that one of the methods for rapid quality evaluation is an ATD analysis of the sample solidification process, where samples are taken from different areas of the master heat ingot. The evaluation is based on a set of parameters plotted on the graph of the dT/dt derivative curve during the last stage of the solidification process in a range from TEut to Tsol.

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Self-Compassion and Quality of Life in Adults Who Stutter

American Journal of Speech-Language Pathology ◽

10.1044/2020_ajslp-20-00055 ◽

2020 ◽

Vol 29 (4) ◽

pp. 2097-2108

Author(s):

Robyn L. Croft ◽

Courtney T. Byrd

Keyword(s):

Quality Of Life ◽

Social Connectedness ◽

The Self ◽

Future Research ◽

Self Compassion ◽

Adults Who Stutter ◽

And Gender ◽

Relationship Of ◽

The Impact

Purpose The purpose of this study was to identify levels of self-compassion in adults who do and do not stutter and to determine whether self-compassion predicts the impact of stuttering on quality of life in adults who stutter. Method Participants included 140 adults who do and do not stutter matched for age and gender. All participants completed the Self-Compassion Scale. Adults who stutter also completed the Overall Assessment of the Speaker's Experience of Stuttering. Data were analyzed for self-compassion differences between and within adults who do and do not stutter and to predict self-compassion on quality of life in adults who stutter. Results Adults who do and do not stutter exhibited no significant differences in total self-compassion, regardless of participant gender. A simple linear regression of the total self-compassion score and total Overall Assessment of the Speaker's Experience of Stuttering score showed a significant, negative linear relationship of self-compassion predicting the impact of stuttering on quality of life. Conclusions Data suggest that higher levels of self-kindness, mindfulness, and social connectedness (i.e., self-compassion) are related to reduced negative reactions to stuttering, an increased participation in daily communication situations, and an improved overall quality of life. Future research should replicate current findings and identify moderators of the self-compassion–quality of life relationship.

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Surgery for Lung Cancer and the Consequences for the Swallow

Perspectives of the ASHA Special Interest Groups ◽

10.1044/persp1.sig13.162 ◽

2016 ◽

Vol 1 (13) ◽

pp. 162-168

Author(s):

Pippa Hales ◽

Corinne Mossey-Gaston

Keyword(s):

Lung Cancer ◽

Treatment Options ◽

Vocal Cord Palsy ◽

Subsequent Treatment ◽

Physiological Reserve ◽

Palliative Phase ◽

And Function ◽

The Impact ◽

Swallow Function

Lung cancer is one of the most commonly diagnosed cancers across Northern America and Europe. Treatment options offered are dependent on the type of cancer, the location of the tumor, the staging, and the overall health of the person. When surgery for lung cancer is offered, difficulty swallowing is a potential complication that can have several influencing factors. Surgical interaction with the recurrent laryngeal nerve (RLN) can lead to unilateral vocal cord palsy, altering swallow function and safety. Understanding whether the RLN has been preserved, damaged, or sacrificed is integral to understanding the effect on the swallow and the subsequent treatment options available. There is also the risk of post-surgical reduction of physiological reserve, which can reduce the strength and function of the swallow in addition to any surgery specific complications. As lung cancer has a limited prognosis, the clinician must also factor in the palliative phase, as this can further increase the burden of an already compromised swallow. By understanding the surgery and the implications this may have for the swallow, there is the potential to reduce the impact of post-surgical complications and so improve quality of life (QOL) for people with lung cancer.

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