Ceramic Shell Casting

 

A Comprehensive Analysis of Viscosity Measurements

2019 - ICI

• This paper will present a comprehensive analysis on the impact these variations have to the accuracy and precision of the viscosity measurement; specifically exploring results from various flow cups, end points, operators and slurry types.

 

How Process Variables Impact Ceramic Shell Properties and Performance

2018 - ICI

• This paper will look at how process variables, such as slurry properties and dipping/draining techniques, impact ceramic shell properties and performance. Information on how process variables impact shell properties will prove useful when setting up process control for shell building.

 

The Impact of High Performance Additives to Slurries with Aluminosilicate Refractories Technical and Economic Effects

2017 - ISIC

• This paper will review high performance slurry additives and the impact they have on shell properties. In addition, the impact these materials have on the process and overall cost of casting will be examined in detail.

 

Improving Efficiency and Results with Systematic Approach to Process and Problem Resolution

2015 - ICI

• This paper discusses the implementation of formalized problem resolution methods within an organization. It demonstrates the value of a common language across multiple functions. It also provides case studies showcasing the results of implementing a decision-making/problem-solving tool. Case studies focus on situation appraisal to smoothly implement new product into production; decision analysis to bring a product solution to a customer foundry; and problem-solving to identify foundry process issues impacting results.

 

Evaluating Spalling Factors through Measuring Intercoat Adhesion

2014 - ICI

• This paper focuses on the development and application of a testing method to measure the weakest adhesion point of a ceramic shell sample. The resulting test can be used to isolate ceramic shell construction variables that affect intercoat adhesion of ceramic shell layers. Utilizing this method, a foundry can optimize the slurry shell building process to reduce the potential for spalling defects on their castings. This test can be employed on a small scale without the need to jeopardize standard production.

 

The Use and Application of Ceramic Core Fill Materials

2013 - ICI

• This paper will discuss methods available to investment casters utilizing pourable core materials.  Proper application techniques and common issues will be addressed, along with case studies analyzing the process and economic benefits obtained utilizing available core materials. 

 

Improving Process Efficiency Through Customer/Supplier Collaboration

2011 - ICI

• This paper explores the issues that face investment foundries including their needs to reduce costs and to improve overall efficiencies of their operations with specific focus on their shell rooms. An analysis of the process and economic benefits obtained by using new generation technology along with application expertise is examined.

 

How Ceramic Shell Properties Predict Resistance to Shell Cracking

2010 - ICI

• This paper introduces a method for measuring the crack potential of a shell, and continues the work presented last year where a new look at green shell permeability was introduced as a meaningful shell characterization tool. With a repeatable shell cracking model developed, a shell’s properties can be correlated to shell dewax performance.

 

A New Look at Shell Permeability and the Factors That Impact It

2009 - ICI

• This paper shows that shell permeability can also be improved through changes in the backup shell system. By evaluating various primary and backup systems; the potential impact of each layer on overall shell permeability is determined. Shell permeability is analyzed in both the green and hot states, with relevant data and results being used to support the theories.

 

Foundry Perspectives: Process and Economic Benefits Through Improved Shell Processing and Technology

2008 - ICI

• This paper will explore the issues that faced investment foundries including their needs to reduce costs and to improve the overall efficiencies of their operations with specific focus on their shell rooms. By using new generation technology along with application expertise, these foundries were able to improve operations and gain both process and economic benefits.

 

An Evaluation of Methods Used to Determine Shell Strength and How a Material will Perform in the Dewax Process

2007 - ICI

• This paper will evaluate the methods that are used to characterize the strength of shell molds in the green, or prefired, condition. It will also look at various shell material components and how they impact the results of the various test methods that have been used or proposed. The authors will relate the scientific strength measurement techniques to practical tests and experiences so that conclusions can be drawn regarding the various test methods and how they predict how a shell material will perform in the process, especially the autoclave dewax process. Various shell materials and components will be analyzed for this paper.

 

The Development and Application of a Specialty Colloidal Silica Sol for High Temperature Applications

2006 - ICI

• This paper will compare the specialty colloidal silica binder to traditional colloidal silica sol. Laboratory test data will be presented to highlight the above properties. Information on the process of converting to this new binder will be presented. This information will highlight the benefits of this binder to the existing process and will also present some of the hurdles that needed to be cleared in order to completely implement the binder into production.

 

Energy Efficiency in the Investment Casting Foundry

2001 - PKI

• This paper addresses energy conservation in shell dewax, burnout and preheat. Comparisons made between different types of equipment (pusher vs. box furnaces, electric vs. gas-fired furnaces, etc.) and different process options (continuous vs. batch operations, autoclave and burnout vs. FlashFire Dewax). Methods for evaluating and improving energy efficiency in the foundry are discussed (with energy saving tips).

 

Practical Ceramic Shell Slurry Preparation and Control

2001 - 25th BICTA Conference

• This paper presents a practical review of slurry makeup and control. The purpose of this paper is to review, remind and in some cases instruct, the foundry as to the basics that should be followed, or at least considered, in the shell room.

 

Advancements in Polymer Enhanced Water Based Primary Binders and Slurries

2001

• This paper discusses an advanced polymer enhanced primary binder that provides significant benefits to the Precision Investment Casting (PIC) industry. Detailed testing, both from the laboratory and from production environments, is presented to show how this binder offers improved slurry life, excellent wetting properties and better stability.

 

Ceramic Shell Green Strength - How is it Measured and What does it Mean?

1999/2000

• This paper evaluates various binder and refractory systems for the green shell strength. The results are compared using both traditional and alternative measuring techniques.

 

Hot MOR and Creep Properties of Common Ceramic Shell Refractories

1999

• This paper will present the hot strength properties of common refractories used in the PIC industry. It will also show baseline data for hot strength properties of common refractory materials. In addition, the effect that particle size, refractory chemistry, refractory blend and burnout cycles have on the hot strength will be explored.

 

Shell Material Consumption: How to Determine Actual Weights and Costs by Components

1998 - April - INCAST Article

• In the PIC market there are often costs that are overlooked or considered to be undeterminable. This could be of concern when trying to determine what price to quote a potential customer for a given casting. This paper provides a method for determining actual shell cost for a part.

 

New Developments in Rapid Dry Water Based Shell Systems

1994

• This paper examines an innovative water based system that can be customized to conform to specific needs or parameters within a given foundry. These include both process and economic factors. The result is a unique material with application flexibility that can easily achieve a myriad of benefits. Laboratory and foundry data for various applications is reviewed. 

 

Improvements in Ceramic Shell Technology Resulting from Environmental Pressures

1993 - September - Foundry Trade Journal

• Environmental legislation, as opposed to pressure groups, first began to impact on investment casting foundries in the USA over five years ago; principally by introducing limits on the emissions of volatile organic compounds (VOCs) such as the alcohol solvents used for ethyl silicate based binder systems. 

 

Thermal Conductivity and Heat Transfer Measurement for Ceramic Shell Molds

1992

• This paper describes a measurement technique to compare thermal transfer properties of ceramic shell systems. Technique would give a relative thermal conductivity and heat flow figures. Data on common shell materials is also provided. 

 

An Analysis of Ceramic Shell Materials

1990 - June - 21st EICF

• This paper looks at various binders and refractories and determines how they affect the properties of the ceramic shell and the investment casting process.

 

Getting More from Your Ceramic Shell Slurry

1990 - August - Modern Casting Article

• Ceramic shell slurries are the lifeblood of the PIC industry. They literally shape the industry's products. They also significantly measure the success of the investment casting foundry because without good quality slurries, quality production of castings is impossible.

 

Jewelry Casting

 

Effects of Changing the Water-to-Powder Ratio on Jewelry Investments

• This paper explores how the various properties of a gypsum-bonded investment change as a function of the water-to-powder ratio. This paper also discusses how these changes can affect mold and casting attributes and reinforces the importance of using the water-to-powder ratio range set by investment manufacturers.

 

Effects of Water Quality and Temperature on Investment Casting Powders

• This paper explores how variations in water quality and temperature impact the properties of the mixed investment. Water from a variety of sources is evaluated. In addition, proper process control to negate the impact of water quality and temperature is presented.

 

How Process Variables Impact Investment Removal Properties

2019 - Santa Fe

• Utilizing the Design of Experiment (DOE) process, this paper will look at the effects that certain controllable process and procedural factors have on the quench results when quenching gypsum based jewelry investments.