News
Articles
What Causes Shell Cracking in the Investment Casting Process?
Cracking is the number one problem faced by investment casters. What is to blame – the shell or the wax? The truth is found when we look at the entire system. A recent study showed the effect of three variables on shell cracking: viscosity of non-filled pattern wax, particle size distributions, and the total number of prime dips.
So the question remains: How much is wax responsible for shell cracking? How much can we blame prime permeability? When a second prime dip is added, what is the loss of permeability?
For successful de-waxing, investment casters believe that one or both of the following conditions are required.
1. Low viscosity wax must be used at autoclave temperatures to allow the wax to melt and exit before it expands and puts tension on the shell.
2. Wax should soak into the shell when the prime and intermediate layer are permeable.
Based on laboratory testing, we conclude that wax viscosity has the greatest effect on shell cracking. The higher the viscosity, the more the shell will crack.
The Development of a New Soluble Wax
- Improved surface
- Short dwell times
- Overall strength
- Fast leach
We hoped to address the issues plaguing soluble core material and discovered the durability of the new soluble wax could be designed without fibers. Less crazing, cracking, and flow lines ensued without the hassle of fibers. Upon cooling, we allowed the injection of very large parts, cylindrical shapes, and intricate small cores. Fibers could still be added without affecting viscosity when extreme situations called for unusual strength.The most impressive find was that the material dissolved up to 50% faster than most soluble wax formulas.
Events
Technical Conference & Equipment Expo
The Westech Wax Products team will be attending the 61st Annual Technical Conference & Equipment Expo in Covington, Kentucky from October 6-7, 2014. We look forward to presenting our newest line of industrial wax, sheet wax, and casting supplies to the investment casting industry.
Investment Casting Institute
If your company is a member of the Investment Casting Institute, consider participating in the Investment Casting Specialist Industry Certification Course taking place at Pittsburg State University in Pittsburg, KS. The leaders at Westech were involved in the creation of the curriculum, so if you’d like to become an expert in the investment casting process, sign up today. More information can be found at www.investmentcasting.org/training.asp.
Awards
Westech Wax Products is proud to announce our ISO 9000 certification. This is a great honor that requires our company to uphold the highest level of quality management. In accordance to certification requirements, we will continue to improve upon the quality of our products and services.
Investment Casting Institute
If your company is a member of the Investment Casting Institute, consider participating in the Investment Casting Specialist Industry Certification Course taking place at Pittsburg State University in Pittsburg, KS. The leaders at Westech were involved in the creation of the curriculum, so if you’d like to become an expert in the investment casting process, sign up today. More information can be found at www.investmentcasting.org/training.asp.