| | Category | ENEV | P18 | Mat Innovation for Mounting Ceramic Substrates |
| | Abstract | My project is a Mat Innovation that is used for mounting ceramic |
| | substrates in automotive emission control devices. |
| | A catalytic converter is made up of a substrate, mat and metal shell- |
| | housing. The mat has to provide enough holding force to counter the |
| | back pressure and acceleration forces the substrate will experience |
| | while not exceeding the isostatic strength of the substrate. |
| | In a previous project I had designed an automotive particulate filter that |
| | had lower back pressure than the filters in production today. Prototype |
| | sample testing confirmed the benefits of my innovation. Use of this filter |
| | design could save millions of gallons of fuel each year. |
| | However, my triangular cell filter innovation could not go into production |
| | due to its strength limitation. This filter has lower isostatic strength and |
| | cannot withstand the canning process. |
| | This was the motivation of my Mat Innovation project. I decided to invent |
| | a support Mat that provided the holding force at much lower peak |
| | canning pressures, thereby avoid crushing the weaker substrates. I first |
| | researched the properties and performance characteristics of the |
| | existing mats in the market. Using the force balance, I calculated the |
| | holding force required for a hypothetical filter. Then using the peak |
| | pressure curves of available mats, calculated the pressure the |
| | substrate will experience to achieve the desired holding force. |
| | Out of the 16 mats that I investigated, only 5 mats passed the |
| | hypothetical case study which was purposely less severe than the |
| | actual requirements otherwise no existing mat would have passed. The |
| | mats failed either due to high peak pressure or insufficient holding |
| | force. |
| | Next, I identified all the critical common features of these down selected |
| | mats. I concluded that polycrystalline non-intumescent low binder mats |
| | and hybrid mats with low vermiculite performed the best. |
| | High coefficient of friction also allows achieving the required holding |
| | force at lower peak pressures. I decided to increase my mat’s |
| | coefficient of friction by adding fine silica on the surface of the mat and |
| | by providing a texture to the mat during manufacturing. |
| | I created a prototype mat design with the identified desirable features. |
| | In this polycrystalline non-intumescent hybrid mat I decided to keep the |
| | vermiculite on the ceramic side so it heats up faster and fixed the 200 |
| | micron fine silica using an adhesive. 3M provided technical support in |
| | making the prototype sample. |
| | Testing showed that the peak pressure data of the novel mat was |
| | marginally lower than the currently available mats. Due to the |
| | optimization of binder, vermiculite etc. I had expected significantly lower |
| | peak pressures. However, the coefficient of friction was significantly |
| | higher as expected. Using this information I recalculated the safety |
| | factor and peak pressures and this novel mat out performed all |
| | currently available mats. |
| | This novel mat will provide sufficient holding force for the real world |
| | pressure and acceleration forces without crushing the innovative filter |
| | and other thin wall substrates. My mat innovation will allow low back |
| | pressure substrates to go into automotive production saving millions of |
| | gallons of fuel! |