Machinability_poster
1 / 1Seiten

MACHINABILITY & WORKPIECE MATERIAL PROPERTIES OUR MAIN TARGET: LINK WORKPIECE MATERIAL PROPERTIES TO MACHINABILITY 1. WORKPIECE MATERIAL PROPERTIES 2. WORKPIECE MATERIAL CLASSIFICATION (SMG VERS. 2) ISO MAT. GROUP Main workpiece material property Most important with materials Biggest machinability issue Average material properties Achieve conditions for free cutting (energy eficient machining) High hardness High mechanical and thermal loads on the cutting edges High abrasiveness ISO-K / ISO-S High scratching effects on the cutting surfaces High adhesion tendency and ductility ISO-M / ISO-S / ISO-N Bad chip formation and formation of built-up edge on the cutting edge High strain hardening factor ISO-M / ISO-S Local high loads on cutting edges ISO-M / ISO-S High temperatures in the cutting zone 3. MACHINABILITY POLAR DIAGRAMME A machinability polar diagramme visualises the influence of five important material properties on the machinability. Below is an example for Inconel 718. In this example can be observed that mainly the high strain hardening and the low thermal conductivity of this material determines the machinability of the material. Adhesion 100% 80% 60% 40% Strain hardening 1. THIS MATERIAL PROPERTY: High adhesion / ductility High strain hardening tendency High hardness High abrasiveness High localised loads High temperatures in cutting zone High mechanical and thermal loads Micro chipping (BUE) Flaking, notch wear Plastic deformation Chipping / notching Plastic deformation High wear rate Plastic deformation Chipping / breakage Flank - crater wear Notching 3. ... LEADS TO Tool wear 4. GENERAL RECOMMENDATIONS FOR TOOL SELECTION AND CUTTING CONDITION SELECTION Cutting material Toughness Tough coating High compressive strength Hard or tough (feed dependant) Abrasion resistance Cutting conditions Temperature control Low cutting speed High feed and DOC Low cutting speed and feed Low speed and feed High DOC Cutting geometry Sharp edge radius High rake angle Small nose radius Adapted cutting edge geometry High rake angle, strong cutting point and edge Small rake angle Cutting edge strength This overview represents a generic approach to link workpiece material properties to general machinability rating. For more detailed analysis of machinability ratings for specific workpiece materials, please contact your business partner at Se