New Trend On Plastic Replacing Metal
2016-01-22 admin
3176Click
The continuous improvement in engineering plastics brings more and more cases of plastics replacing metal. New generation fibers reinforced plastics, such as Sovay IXEF, are competitive to metal in terms of mechanical properties. Besides, IXEF injection parts has surface so smooth and defect free that it can be used in structural appearance. Some Solvay Amodel PPA grades with heat deformation temperature up to 310C, and resistant to hydrolysis can be used in high temperature and humid environment. Long fiber reinforced plastics has drawn much attention recently. Fibers retain its length and tangled in finish articles, making the finish articles have high rigidity and flexibility. With other advantages like dimensional stability, light weight and corrosion proof, long fiber reinforced plastics have been widely used in automotive, aeroplane, medical, transportation and sports devices, appliance, and electrical parts. Plastic parts account for 16% weight in current vehicle. First Foundation Ltd. Estimates that the weight percentage will gradually goes up to 25% in 5 years, making new generation vehicle more fuel-efficient, less carbon emission and more comfortable.
Benefits Of Plastic Replacing Metal
Although different plastics are used to replace metals for different reasons, here are the common benefits of replacing metal parts with plastic ones:
1.Weight reduction: plastic parts yield lower density (1.7) than iron (7.8) and aluminum (2.8) ones. Carbon fiber reinforced plastic is generally more efficient in weight reduction.
2.Chemical resistance: Chemical resistant plastics make them more resistant to corrosion, rain and detergent substances than metals.
3.Reduced system cost: plastic requires minimal assembly and allow for reduce part count, and reduced secondary operations such as welding, painting and laser marking.
4.Suitable complex parts: a single plastic injection molded part can replace complex multiple metal pieces and reduces additional assembly of metal parts.
5.Enhanced Design freedom: plastics provide the flexibility to use complex geometry. Flexible shape design makes brand or product unique.
6.Reduced scrap: plastics minimize multiple processes. In some cases, start-up or scrap parts are allowed as regrind for the application or scrap is utilized in other plastics through reprocessing.
7.Shock absorption: plastic parts are effective in absorbing shock and noise, making products more quiet and durable.
Procedure of Plastic Replacing Metal
The first step is to determine which metal parts can be replaced by plastic ones. Evaluate the cost on all the existing design functions and processes. The general rule is that the parts not involving rotation, sliding or handling during operation can be integrated into fewer parts. These parts are suitable for replaced by plastics. On assembly, the screw design can be minimized or substituted by snap fit, ultrasound or other assembled methods. Finite element analysis (FEA) can be preliminarily applied in design to assess the force status and safety factor of plastic parts in use. Computerized software lick mold-filling analysis (MFA) can be used to analyze stress distribution in mold design and parameters selection. It also helps optimize finish parts and production process to achieve highest economic efficiency.