Armin Bijanzad 12th WEEK unanswered

1.Open mold casting

An indentation is made from a piece called the model,master model, or master which produces the inverse of the product's shape(contreform).The mold produced will be made of a refractory material when casting metal or metallic alloys, plaster for casting plaster or resin, steel for casting glass, and thermoset resin reinforced with fibers for casting resin and plaster.A new generation of silicone molds is now being developed which bypass the need for back-tapering(draft angles) and release agents.Apart from silicone, all molds need release agents, which prevent the pieces sticking to the mold.Liquid matter can be cast very easily using just the force of gravity.One side of the piece is exposed to air.In the case of thermoset resin , the use of a catalyst solidifies the piece.For other materials, hardening occurs due to evaporation or cooling.
(materiology by Daniel kula and elodie ternaux p.279)

2.Plastic calendering

The plastic is heated and rolled between two or more rollers until it forms a continuous sheet.In terms of production, calendering is viable from 1000000-m upwards.
calendering has a number of variations, according to the materials used and the desired result.The technique will eventually include the effects gained by die-stamping(artificial leather effect, for example), printing, coating of metallic films and etc.
(materiology by Daniel kula and elodie ternaux p.283)

3.Electrochroming

Electrolysis consists of chemical decomposition due to the effects of an electric current.An anode and a cathode are placed in a tank filled with a solution , and linked to a continuous current generator.The anode is the positive terminal, and the cathode, negative.The anode undergoes reactions of oxidation, and will loose electrons, whereas the cathode undergoes reaction of reduction and gains electrons.
By electrolysis , pieces of plastic can be coated in chrome, nickel, and even gold.The metal is deposited in the solution and the plastic pieces need to be made conductive (ABS,Polypropylene,polyamide,polycarbonate, for example). The pieces , submerged in the bath, act as the cathode and will be covered in the metal on all surfaces.It is possible to make quite large pieces (for cars, for example )
(materiology by Daniel kula and elodie ternaux p.306)

4.Hot marking

A plastic film with metallic deposits in inserted between a heated die punch and the piece to be decorated.The pattern, machined in relief on the die, is transferred by pressure and heat onto the piece(which may be plastic, for example).This procedure is fast, simple, and economical.Hot marking is often used to obtain 'gold' and 'silver' logos on cosmetic cases or flocked packaging.Gilding(with gold leaf) when done on luxury leather objects is similar to this thechnique.
(materiology by Daniel kula and elodie ternaux p.307)

5.Copolymers

Nowadays there is a general tendency towards having 'alloys'.The main objective is to unify the positive properties without combining the bad ones.The mixture is not intimate, it is more of a co-existence.
Polymers are no exception to the rule, which is why we are witnessing an increase in the number of copolymers.A current famous example is ABS, Acrylonitrile-Butadiene-styrene, used for interior automotive components such as dashboards or door handles and mobile phone and vaccum cleaner bodies.The copolymer
polypropylene-polymide(pp-pa) is also widely used in the field of automotive manufacturing for rear-view mirrors and bodywork parts.
(materiology by Daniel kula and elodie ternaux p.68)