Wednesday 3rd January 2018
CFC (Carbon Fibre Composite) is widely used for high temperature applications, as part of charge grids, fixtures and furnace furniture. It represents the optimum material for jigs and fixtures within the heat treatment process due to its high mechanical strength, high flexural strength, low thermal expansion, thermal shock resistance and its lightweight nature. Fields of application in the sector include heating elements and charging systems. Historically the most commonly used materials for furnace fixtures are metallic based alloys. Initially this will have been due to there not being a viable, consistent alternative and therefore metallic fixtures became the default option. However, over recent years end users have seen the benefits of CFC for their charging system needs, and increasingly after they test out the use of CFC within a furnace application, they are quickly adopting it as their preferred material of choice for all further applications. Here, we explore 3 reasons why:
CFC is a lightweight yet extremely strong product and it becomes more mechanically strong with higher temperatures. As a result of its reduced weight, a customer using CFC can load more components within the furnace and maximize the yield for each charge, increasing productivity efficiencies. In situations where more parts cannot be loaded due to component size, CFC can still provide tangible benefits. A typical CFC fixture is between 10% - 20% the weight of a metallic fixture, meaning customers can benefit from a quicker process time and subsequent energy savings due to lower overall thermal mass. Another benefit of CFC is that it will not warp after time in use; the same guarantee cannot be provided with metallic jigs and fixtures. For example, if a company is making parts and have difficulty maintaining the integrity of the shape during heat treatment, they should consider a CFC fixture for their needs. Bespoke designs around even the most difficult to hold parts are a core strength of Erodex, particularly within aerospace applications.
CFC has had reputation as being expensive, leading to it being disregarded as an option by some people. However, if you look into its use more deeply, there are actually significant cost savings to be made. As we discussed earlier, metallic fixtures can warp after as little as 6 months and should the warp cause a part to be scrapped, that is another cost that would be incurred. This may not be an issue for all users, but for some it will. On top of this, metallic fixtures will need maintenance to repair them or will need replacing regularly. Over time these costs add up. In contrast, a correctly designed CFC fixture, with good housekeeping, can last many years. Maintenance costs would be minimal – a CFC strut or bolt here and there, rather than a whole new fixture. Return on investment on CFC fixtures can also be extremely quick. For example, within a recent project an Erodex client received a payback on a £20,000 CFC fixture within 1.5 days. They were initially being charged per run for subcontract heat treating and achieving a rate of only 6 parts per run. After discussing their requirements with Erodex, the customer received a bespoke fixture for use in house that could treat 24 parts per run. That, coupled with not having to subcontract meant ROI was achieved very quickly. Throw in the significantly increased life span of the fixture itself, and it becomes clear that the financial benefits are considerable.
Erodex have 3 different grades of CFC, each with their own suited application: Standard (suited for heating elements, furnace linings and some charging systems) Performance (a demonstrably stronger grade of CFC, It is the go to grade for our charging systems and also for use in oil quenching applications, where low porosity leads to 33% less oil absorption) Mechanical (suited for connection elements such as nuts and bolts or small bespoke items).
The Erodex Group specialise in the bespoke use of Carbon Fibre Composites for high temperature applications. To speak to one of our expert advisers in this field, email firstname.lastname@example.org and we will be in touch within 24 hours. Click here to see our high temperature product page