PRESS2010_EN

1110/1208

PositionHardness2700HVPosition700HVSection detailsIn January 2006, Punch Industry started to vend F coating punches for high tensile material, which were widely used by most customers in high-frequent punching performance with very good comment. On the other hand, it was also required by most customers to list the［Comparison of Punching Performance between Punches with F Coating and others］. In view of this requirement, a stamping mold was designed to evaluate the durability of F coating punches for high tensile material. WorkpieceWidth×Thickness100×1.6ClearanceSlanted angle of workpiece3 degrees（refer to Drawing 4）No. of strokesTip shapeTypeF coating is a composite surface treatment based on PVD treatment （Physical Vapor Deposition）, which can improve the features and durability of a punch through improved coating layer density and impact resistance. For F coating punches, the surface treatment method is the same as the one of existing products—PVD treatment （TiCN）. However, the surface of base material is hardened through special treatment （drawing 1）. This can effectively reduce the breakage of coating layer caused by base material deformation. On the other hand, the adhesiveness of F coating is greatly enhanced when compare with existing coating layers （drawing 2）. With the two features listed above, the potential of coating layer is maximized, and the lifespan of punches is greatly improved.In Drawing 3 of testing die set, 8 punches are tested in the same condition （refer to drawing 4）.In order to receive the result quickly, the workpiece is slanted for 3°, and the single-side clearance is set as 3%. Other punching conditions are listed in the table below.TD and WPC＋TiCN were selected from surface treatments that applicable to high tensile material, in order to compare with F coating. the base material are identical SKD11（60〜63HRC）, and the features of different coating layers are listed in table 1. For every 2000 shots, the testing die set was disassembled from stamping machine, and the coating layers in punch tips are examined. pictures are taken from 3 different aspects of the retainer （picture 8）.TypeSurface treatmentSPC780DU（High tensile material 780MPa）Mounting methodRetainer is applied3％（Single-side）Round, φ10.2mmEjector punches with centre holeShotsLead-in lengthStamping machineAIDA 150ton5mm into the button die55spmNo10,000 shotsLubrication1108F coatingSurface alteration＋Physical vapor deposition（PVD）TDTD processThickness（μm）2〜34〜72〜3Hardness（HV）2700 or more3200 or more2700 or moreDrawing 1／Section of different coating layersDrawing 2／Shock resistance is improved after special treatmentDrawing 3／Testing die setDrawing 4／Ichnography of testing die setInstructions and features of F coatingIntroduction of the testStandard and evaluation of testWPC＋TiCNSurface alteration＋Physical vapor deposition（PVD）Table 1／Testing coating layersExisting coatingCoating layerBaseCoating layerBase materialExisting productsDeformation of base material causes breakage of coating layer.F coatingSpecialtreatmentTiCNmaterialBasematerialTiCNSpecialtreatmentBase materialF coatingThe base material is hardened after special treatment, and breakage of coating layer hardly happen.Comparison of F Coating Punches for High Tensile Material