Materials, modes and methodologies for advanced engineering
Demands for improved, cheap, and better methods and materials are the market realities of modern engineering and materials science. New materials are coming on the market regularly, and to design engineers, these are always interesting developments. That said, all engineers tend to believe in wonder products after they’ve seen some proof .
In the questioning world of professional engineering, nothing is simply accepted on face value. Questions will be pointed and practical, and will relate to functional issues across a spectrum of relevant points from machining materials to stress and other highly important matters.
There’s also some market resistance. An “advanced” product might not fit working techniques and preferred standards. For example, joining heterogeneous materials involves some unavoidable issues:
- Compatible joining methods and characteristics
- Stress focus and issues with component substrates;
- Composites may not respond well to drilling and possible damage to fibres, reducing strength;
- Thermal issues and contraction rates of heterogeneous materials may make types of application inappropriate ;
- Methodology issues– A classic engineering situation, finding solutions and cost savings.
The short answer in any practical context is adhesives. Most motorists don’t know their cars are held together with glue. As a matter of fact, this is the best way of joining advanced materials. The record breaking Thrust SSC car used high quality adhesives within the engine and the major structures. Ironically, some adhesives are made specifically to resemble welding or brazing for no other reason but to look “right” to consumers. Actually, many familiar objects like phones and razors are constructed with adhesives .
There are advantages in using adhesives:
- Improved stress management between elements;
- Better, smoother finishes are easy to produce;
- The weight factor, often a key issue in mechanical situations;
- Highly manageable strength, cure rate and customized application methods to streamline and tailor production.
Cost-benefits including faster production process and reduced reworking requirements.
For best and dependable bonding, some substrates need surface preparation. Substances like polypropylene and polyethylene have low surface energy. These materials don’t bond easily. It is possible to treat them with flame, corona and other methods, but those are costly options. Adhesive manufacturers have therefore created primers for use prior to adhesive application. These are simple, brush-on, and cheaper options. They provide a production-friendly, low-cost way of attaining top quality bonds. Aluminium alloys are another instance of a need for preparation for adhesives. Aluminium is a particularly popular, high performance material, and joining needs to be efficient and reliable. Removal of the oxidised surface layer on non-anodised surfaces before bonding is necessary. There are several methods, including abrasion, grit-blasting or acid etch methods are the simple options .
Adhesive research is remaining as progressive and forward-looking as the advances in engineering materials. Regulations such as the Vehicle End of Life Directive have affected material usage in the auto industry which has in turn created a demand for top quality adhesives able to deal with these materials, notably the famous “Green” PVC and the new self-reinforced polypropylene (SrPP). With these new options come new challenges. The demand now is for even more advanced adhesives to bond the new materials. New RoHS and WEEE requirements mean adhesives must be statutorily compliant. Other approvals frequently required include potable water, gas, oxygen and medically compatible adhesives.
If you have some questions or need to know more about bonding and issues related to advanced engineering materials, or need more information about adhesives and benefits for your business, please contact Permabond (tel. 0800 975 9800 or e-mail email@example.com ).