Sandvik Finemac free-cutting wire (Wire)

Transcription

1 Datasheet updated :04:46 (supersedes all previus editins) Sandvik Finemac free-cutting wire (Wire) Sandvik Finemac is a lead free, hardenable, free cutting carbn steel characterized by excellent machinability and high hardness, high wear resistance and exceptinal dimensinal stability after hardening. Hardening peratins are very much simplified cmpared t Sandvik 20AP, wing t the wider temperature and time range available using Sandvik Finemac. This results in significantly reduced failure rates during hardening. Sandvik Finemac als exhibits very gd cld heading prperties. The material is suitable fr lng, narrw cmpnents with tight tlerances. Service temperature 50 t 100 C ( 55 t 210 F). Prlnged service at elevated temperatures causes decreased hardness when used in the hardened and tempered cnditin. CHEMICAL COMPOSITION (NOMINAL) % C Si Mn P S Cr FORMS OF SUPPLY Frms f supply/ finishes Diameter Cu Sn cating Standard tlerance Length, m Straightened wire Drawn D D D2 3 2 Drawn/grund h7 2 Drawn/grund h7 3 Ovality: Fr D1 and D2, max. 50% f the tlerance width: fr D3 max. 25% f the tlerance width: D4 vality in accrdance with the tlerance table belw. Diameter Diameter tlerance D1 +/ D2 +/ D3 +/ D4 +/ Ovality fr D MECHANICAL PROPERTIES

2 Frms f supply/finishes Diameter Tensile strength Rm 1) MPa Wire in cils Drawn >980 Straightened wire Drawn >1000 Drawn/grund ) Nminal values. Other prperties n request. >980 >980 Impact strength Observe that the quenching time and temperature are dependent n dimensin. Specimens fr the Charpy V impact strength test are larger than standard wire dimensins. Table f impact strength fr Sandvik Finemac, hardened and quenched cnditin. See Figure 1. Saking temperature 810 C (1490 F), saking time 4 min, tempering time 30 min. Tempering temperature, C Impact strength, J Figure 1. Impact strength after recended hardening prcedures, valid fr all dimensins. Saking time 30 minutes. Standard Charpy V specimens at 20 C (68 F). PHYSICAL PROPERTIES DENSITY Cast billets g/cm, 0.28 lb/in Resistivity Cld drawn and tempered 0.20 µωm at 22 C

3 1) THERMAL EXPANSION Temperature, C Cld drawn and tempered ) Mean values in temperature ranges (x10 6) Sandvik Finemac is a magnetic material. HEAT TREATMENT Sft-annealing When required, sft annealing shuld be cnducted fr a perid f ne hur at a temperature f C ( F). HARDENING Diameter Temperature Saking time Quenching C apprx. min in il at 50 C > in water The smaller the diameter, the shrter the saking time. T avid xidatin and decarburizatin, hardening shuld be cnducted in a prtective gas atmsphere using nitrgen, argn r vacuum. Cntact Sandvik fr advice. Prlnged service at elevated temperatures causes decreased hardness when used in the hardened and tempered cnditin. See als Impact strength under Mechanical prperties. TEMPERING Temperature, C Tempering time, min The cre f the material needs a tempering time f at least 30 minutes. T reduce the risk f cracking, tempering shuld be cnducted iediately after hardening. The heating rate shuld nt be t high, particularly in the case f intricately shaped cmpnents. Hardness Figure 2. Hardness after quenching in il at 50 C (120 F), valid fr all dimensins.

4 Figure 3. Hardness after recended hardening and tempering prcedures, valid fr all dimensins. Tempering time 30 minutes. Hardening peratins Hardening peratins will be very much simplified cmpared t Sandvik 20AP, wing t the wider temperature and time range available using Sandvik Finemac. Scrapping rates during hardening will be greatly reduced. Figure 4. The cling rate f Sandvik Finemac vs. that f Sandvik 20AP. MACHINING The recended values, based n Sandvik Crmant cemented carbide cutting tls r high speed steel tls frm Sandvik, are t be regarded as starting data. T btain the ptimal cmbinatin f finishes, tlerances and prductivity the values shuld be adjusted fr each individual peratin. The data assume the use f a suitable cutting fluid. In machining withut a cutting fluid, the values shuld be reduced by abut 10%. Detailed recendatins can be btained frm yur nearest Sandvik Crmant r Sandvik ffice. In the manufacture f sphisticated precisin cmpnents, the material's highly unifrm and very gd machinability ffers reliable prductin with high prductivity. This is f majr imprtance since cmpnent prcessing csts can be several hundred times greater than the cst f the raw material. Material in the drawn cnditin up t Ø 2.5 has a Cu/Sn surface layer. This layer enables cmpnents t be machined with very high demands n dimensins due t the fact that the guide bushing can be set with very tight tlerances, thereby achieving high accuracy n the finished dimensins. Turning The charts belw give guidance n hw speed and feed affect diameter tlerances and surface rughness f turned cmpnents. The charts are based n lngitudinal turning. The tlerances are given by using the ISO system, i.e. IT7 culd mean h7, k7 r js7.

5 The tls used in Figures 5 8 have been brazed, cemented carbide tls. Brazed tls used: Sandvik Crmant tl 310 L grade H10F, rake angle 0, clearance angle 6 and entering angle 90. Figure 5. Wire diameter 1.20, high tensile strength, drawn cnditin, depth f cut between Brazed cemented carbide. Figure 6. Wire diameter 1.20, medium tensile strength, drawn cnditin depth f cut between Brazed cemented carbide. Figure 7. Wire diameter 3.00, drawn cnditin, depth f cut between Brazed cemented carbide.

6 Figure 8. Wire diameter 3.50, grund cnditin, depth f cut between Brazed cemented carbide. Bar autmatics Diameter > apprx. 2 Tl Cutting speed m/min LONGITUDINAL TURNING AUTOMATICS, PLUNGING AUTOMATICS AND SIMILAR MACHINES Operatin Cutting Feed, Medium depth /rev. 1) 2) Finish turning Rugh turning Single pint turning < Frming Plunge cutting and parting ff > ) Fr parts requiring high precisin. 2) Fr parts with mderate tlerance requirements and parts that subsequently must be finish machined. THREADING Tl Grade Cutting speed m/. Threading dies 3 6 Self pening die heads 5 10 Thread chasers Thread rlling DRILLING Drill Feed Speed diameter, /rev. rpm END MILLING Tl type Grade Cutting speed m/. Indexable insert tls Slid end mills Brazed helical fluted end mills 30 40

7 HOBBING Tl Cutting speed m/min Reaming Cutting speed fr diameters > abut 2 Reamer Grade Cutting speed Straight/helical fluted 10 m/min. Gun drill gemetry FEED Feed /rev. Allwance All data are nminal. Values refer t 20 C (68 F) unless therwise stated. Fr ther requirements and further infrmatin please cntact yur Sandvik ffice. DISCLAIMER: Recendatins are fr guidance nly, and the suitability f a material fr a specific applicatin can be cnfirmed nly when we knw the actual service cnditins. Cntinuus develpment may necessitate changes in technical data withut ntice. This datasheet is nly valid fr Sandvik materials.