Modern Materials
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The world of modern materials Master the highest machining requirements with the new GARANT tools INNOVATION Machining Prices valid up to 31. 07. 2011 EN_1008-00213-Dm-In_england.indd 1 18.11.2010 09:21:14

Modern materials eShop.hoffmann-group.com The material family New challenges in machining ! New material technologies make it possible: Metals, ceramics and polymers can nowadays be mixed or bonded to high performance materials, the composites. This results in completely new challenges to machining, which can optimally be solved with GARANT tools. Steel, quenched and tempered MMC composite Metals Ceramics Inorganic Non-metallic Materials Alloys (metal compounds) Composites Hybrid composite Fibre-reinforced composite Polymers am Blends (polymer compounds) orp ho us Therm oplas e Th r s mo et...

This advertising brochure, its graphic layout and the item numbering system used are protected by copyright. Reprinting and reproduction of any kind - even as extracts - is permitted only with the written consent from Hoffmann GmbH Qualitatswerkzeuge, 81241 Munich, Germany. All prices in £ valid up to 31.07.2011; without guarantee, we reserve the right to correct errors and to make changes.

Modern materials eShop.hoffmann-group.com Glass transition temperature (Tg) Behaviour of plastics under the inuence of heat For machining, the temperature point Tg (glass transition temperature) is of particular importance. Polymers am orp Blends (polymer compounds) ho us Therm oplas set mo er ked Th s-lin s cro tics semi-crystalline amorphous semi-crystalline cross-linked Application area Application area Temperature Tg Tm Tz E-module E-module E-module Application area Temperature Tg Machining of amorphous plastics: only below Tg. If the heating continues, the degradation processs sets in....

INNOVATION Expansion and heat treatment Workpieces true to size due to tempering Expansion coefficient Heat supply L L + Δ L Example: Expansion coecient: The length expansion coecient species the dimensional change, which appears under the inuence of temperature. The change depends on temperature range and material. The unit is 1/K, which species the change per Kelvin or °C. T emperature dierence Material length Expansion coecien t ΔT = 30 K (= 30 °C) L = 500 mm α = 8 · 10 –5 · 1/K ΔL = ΔT · L · α = 30 · 500 · 8 · 10–5 · K · mm = 1.2 mm increase in length K Heat treatment (tempering)...

Modem materials Temperature resistance Thermoplastics differ according to their temperature resistance. The identification of plastics based on external features is much more difficult than for metals. Metals have a characteristic colour. Plastics can look very different due to dyeability.

INNOVATION amorphous n semi-crystalline re tu ra pe m te gh cs Hi asti pl PAI o cti u str s n c Co asti pl rd da s an c St asti pl PEEK PTFE PESU, PPSU PEI PSU ABS, PC, PMMA LCP, PVDF SAN PVC, PS PE, PE-HD PP amo rpho us PP, PPS POM, PA6.6, PA6 lline ta i-crys m se amorphous semi-crystalline transparent brittle chemically unstable tough chemic stable ally fusible 7 EN_1008-00213-Dm-In_england.indd 7 18.11.2010 09:23:59

Modern materials eShop.hoffmann-group.com The E-module ! Important parameters for plastics Definition of the E-module The E-module (modulus of elasticity) describes the plastic's level of stiness . Plastics are tested in a tensile test like metals, but not until they break. The E-module is reached, when the component sample changes, i.e. is no longer linear. Rm Re For plastics a distinction is made between two main groups. Hard brittle (amorphous) plastics behave dierently during the tensile test than tough hard (semi-crystalline) plastics. Hard brittle plastics (amorphous) σR σB Break...

INNOVATION The E-module depending on the fibre orientation If a bre-reinforced plastic is tested in a tensile test across the grain, a lower E-module is present. In direction of the bre, the achieved value is signicantly higher. Multi-directional Uni-directional E-module across the bre orientation 13 000 N/mm2 E-module in bre direction 150 000 N/mm2 Machining direction Fibre orientation and surface protection dene the machining direction and the degree of diculty. 9 EN_1008-00213-Dm-In_england.indd 9 18.11.2010 09:26:07

Thermal and mechanical properties Technical data for thermoplastics and thermoset Description Additives The values for the polyamides are strongly dependent on the moisture content! The table shows a general overview without guarantee of completeness, technical changes reserved.

Chemical resistances Technical data for thermoplastics Chemical substances act on plastics differently. In addition to retention time and mechanical stress, also temperature and concentration have to be considered unconditionally. • = resistant O = par tially resistant The table shows a general overview without guarantee of completeness, technical changes reserved.

odern materials Modern materials - clear and compact Makes (extract) Fibre content % Water absorption % Polyethylene High Density well machinable Po lyet h eret h e rketo n e Tecapeek, Victrex PEEK high tensile and flexural strength, well machinable Aramid aromatic polyaramide fibres Kevlar, Nomex special geometry required, Hostaform, Ultraformt versatile plastic, difficult

Teflon, Kynar,Tecaflon polymers, fibres different materials Metal matrix composite very difficult to machine, only with diamond coating mineral, metalloid/ polycrystalline graphite high conductivity, extremely abrasive, only with diamond feed rates possible honeycombed structure with top layer, metal, polymers, fibres horizjntal materials Carbon fibre thermoset IMS, cyanate ester resin expansion, very abrasive, only with diamond coating

>&> Garant® Overview - Solid carbide jobber drill range - for modern materials Fibre structures Delamination and burr formation, (non-uniform orientation of fibres) Recommended drills: (uniform orientation of fibres) Recommended drills: when using a conventional solid carbide dril solid carbide drills with point angle 140" Solid carbide drills