1、Designation:D312309Standard Test Method forSpiral Flow of Low-Pressure Thermosetting MoldingCompounds1This standard is issued under the fixed designation D3123;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision
2、.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers a procedure for measuring thespiral flow of thermosetting molding compounds(soft or verysoft)designed for moldi
3、ng pressures under 6.9 MPa(1000 psi).It is especially suited for those compounds used for encapsu-lation or other low pressure molding techniques.It involves theuse of a standard spiral flow mold in a transfer molding pressunder specified conditions of applied temperature and pressurewith a controll
4、ed charge mass.1.2 The values stated in SI units are to be regarded asstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determi
5、ne the applica-bility of regulatory limitations prior to use.NOTE1There is no known ISO equivalent to this test method.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD958 Practice for Determining Temperatures of StandardASTM Molds for Test Specimens of Plastics(Withdr
6、awn1995)3E105 Practice for Probability Sampling of Materials3.Terminology3.1 DefinitionsDefinitions in this test method are consis-tent with Terminology D883.4.Significance and Use4.1 The spiral flow of a thermosetting molding compound isa measure of the combined characteristics of fusion underpress
7、ure,melt viscosity,and gelation rate under specificconditions.4.2 This test method is useful as a quality control test and asan acceptance criterion.4.3 This test method,by itself,is not a valid means forcomparing the moldability of similar or different moldingcompounds because it cannot duplicate a
8、ctual conditionsprevalent in different types of production molds.4.4 This test method is presently intended for use at atransfer pressure of 6.9 MPa(1000 psi)and a mold temperatureof 423 6 3 K(150 6 3C(302 6 5F).5.Apparatus5.1 Transfer Molding Press with a minimum 150 by150-mm(6 by 6-in.)platen area
9、,transfer piston pressurepotentially greater than 6.9 MPa(1000 psi),sufficient clamppressure to prevent flashing,and a minimum plunger speed of25.4 mm(1 in.)/s without load.It is recommended that theplunger be equipped with at least one peripheral sealinggroove.It is recommended that a pot diameter
10、between 31.75and 44.45 mm(1.25 and 1.75 in.)be used whenever a choiceis possible.NOTE2Preliminary evidence indicates that,in many cases,reasonablecorrelations may be achieved between laboratories using presses withdifferent pot diameters.Typical examples are presses with pot diameters of31.750,38.10
11、0,and 44.450 mm(1.250,1.500,and 1.750 in.).However,afew well-documented cases are recorded where differences in potdiameters,even within this listed range,have caused large differences inflow-length readings.Therefore,for best interlaboratory correlation it isrecommended that identical pot diameters
12、 be used.5.2 Standard Spiral-Flow Mold shown in Fig.1 shall beutilized.6.Materials6.1 Molding Compound:6.1.1 Any thermosetting molding compound with a spiralflow between 762 and 1270 mm(30 and 50 in.)as determinedat the standard temperature and pressure of this test can beevaluated.1This test method
13、 is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.30 on Thermal Properties(Section D20.30.08).Current edition approved Sept.1,2009.Published September 2009.Originallyapproved in 1972.Last previous edition approved in 2004 as D3123-98(200
14、4).DOI:10.1520/D3123-09.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this histori
15、cal standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 NOTE3Since the only commercially available molds are calibrated ininches,spiral-flo
16、w length will be reported in these units.Conversion to SIunits can readily be made by multiplying the flow length,in inches,by theappropriate conversion factor,25.4 mm/in.NOTE4There is considerable evidence that the test is usable over awider range of flow lengths,but this has not yet been confirmed byinterlaboratory testing.6.1.2 FormThe form of the molding compound shall beloose powder or granules at 296 6 2 K(23 6 2C(73.4 63.6F).NOTE5Preforms or pellets may be used if found necessary;however,
