A kind of metal semi-solid thixotroping molding simulation test unit and method
Technical field
The present invention relates to a kind of metal semi-solid thixotroping molding simulation test unit and method, belong to non-ferrous metals processing field.
Background technology
Semi-solid die casting is the non-ferrous metals processing manufacturing process of a kind of advanced person, and it has the Complex Parts that is easily shaped, and die life is long, drip molding performance advantages of higher.The feature of thixotropic forming is that when not being subject to external force, blank can keep original form and arbitrarily can accommodate transfer, and when by shear stress, blank and for example generally can arbitrarily cut with cream when the blank heating used that is shaped is to semi-solid state.In actual applications, the feature of semi-solid die casting makes it on mould structure and forming technology, have very large difference with plastic yield.Usually when determining material plastic deformation technique, Gleeble simulation test machine can be adopted to analyze material ess-strain feature under different distortion condition, and determine mould structure and technological parameter with this, but after material is in semi-solid state, the structure of Gleeble simulation test machine and working method cannot reflect the feature of thixotropic forming, therefore need a set of being specifically designed to of design to measure the thixotropic simulation test device of material, determine that thixotropic forming mould structure and technique provide foundation for follow-up.
Summary of the invention
The present invention is directed to the problem that existing simulated test facility cannot reflect metal deformation behaviour under semisolid condition, propose a kind of metal semi-solid thixotroping molding simulation test unit and using method, adopt this apparatus and method, accurately can reflect the relation of metal under semisolid condition between the parameter such as deformation temperature, deformation velocity, resistance of deformation, for follow-up thixotropic forming determination thixotropic forming mould structure and technique provide foundation.
For achieving the above object, present invention employs following technical scheme:
A kind of metal semi-solid thixotroping molding simulation test unit, this device comprises pressure mechanism, press down tool heads, shear tool heads, heating arrangement, material carrier platform, sensing device and data acquisition system (DAS) etc., wherein said pressure mechanism is connected with shear tool heads with the described tool heads that presses down respectively, described press down tool heads and shear tool heads can independently be moved under pressure mechanism effect, described material carrier platform places blank, described heating arrangement is positioned at above material carrier platform, can heat blank, described press down tool heads and shear tool heads is positioned at described material carrier platform and the top of heating arrangement, described sensing device is arranged on described pressure mechanism and material carrier platform, described sensing device is connected with described data acquisition system (DAS).
Described pressure mechanism can adopt hydraulic pressure, air pressure or other form to provide pressure, pressure size and to press down speed adjustable within the specific limits.
Described heating arrangement is heater coil, can be induction heating or resistance heated form, and when carrying out test job, blank and material carrier platform are positioned at heater coil inside.
The described tool heads that presses down is two half cylindrical structure, and have gap between two semicolumns, the gap between semicolumn can adjust.
Described shear tool heads presses down between tool heads two half cylindrical structure described, and its shape is sheet, and the large I of specification is selected according to test request.
Described sensing device comprises temperature sensor, pressure transducer, displacement transducer and speed pickup etc.Described pressure transducer, displacement transducer and speed pickup etc. are arranged in pressure mechanism; Described temperature sensor is thermopair, is arranged at the middle part of material carrier platform, and a part for thermopair is exposed to material carrier platform top, perpendicular to material carrier platform, for testing blank temperature.Blank temperature and pressure mechanism are applied to pressure in tool heads and press down speed etc. by sensor transmissions to data acquisition system (DAS), and the signal that above various sensor collects is carried out real time record by data acquisition system (DAS).
Another object of the present invention is to provide the application process of above-mentioned metal semi-solid thixotroping molding simulation test unit.
Adopt said apparatus to carry out the method for metal semi-solid thixotroping molding simulation test, comprise the following steps:
(1) blank to be tested is placed on material carrier platform, and selected shear tool heads;
(2) starting heating arrangement starts blank heating, presses down tool heads simultaneously and is pressed on blank by pressure mechanism with certain pressure;
(3) when blank heating is to semi-solid state, under the pressure pressing down tool heads, the thermopair on material carrier platform is inserted into blank inside, and the temperature signal of inner for blank diverse location is transferred to data acquisition system (DAS);
(4) after blank temperature reaches predetermined trial value, shear tool heads is pressed down with setting speed or set pressure by pressure mechanism, until blank is cut from centre, press down the signals such as pressure in process, speed, displacement and be all transferred to data acquisition system (DAS) by sensing device;
(5) by conversion shear temperature, shear tool heads specification, shear velocity or shear pressure, repeat step (1)-(4), obtain the data of one group of reflection material thixotropic property.
The present invention adopts the above test unit and method, can accurately reflect in metal semisolid blank deformation process, relation between deformation temperature, resistance of deformation, shear velocity and shear mould, for design semi-solid die casting technique provides sufficient theoretical foundation.
Below by the drawings and specific embodiments, the present invention will be further described, but and do not mean that limiting the scope of the invention.
Accompanying drawing explanation
Fig. 1 is the structural representation of test unit of the present invention.
Fig. 2 presses down cross sectional representation when tool heads and shear tool heads fit together in test unit of the present invention.
Main Reference Numerals illustrates:
1 pressure mechanism 2 presses down tool heads
3 shear tool heads 4 heater coils
5 blank 6 thermopairs
7 material carrier platform 8 sensors
9 data collecting instruments
Embodiment
As shown in Figure 1, be the structural representation of test unit of the present invention.Metal semi-solid thixotroping molding simulation test unit of the present invention comprises pressure mechanism 1, be attached thereto connect press down tool heads 2 and shear tool heads 3, be positioned at the heater coil 4 below it and material carrier platform 7, and thermopair 6, multiple sensors 8 and data collecting instrument 9 etc.Material carrier platform 7 is for placing blank 5, heater coil 4 is positioned at above material carrier platform 7, blank 5 between being positioned at wherein can be heated, material carrier platform 7 is provided with thermopair 6, pressure mechanism 1 inside is provided with multiple sensors 8, comprise pressure transducer, speed pickup and displacement transducer etc., thermopair 6 is connected with data collecting instrument 9 respectively by data line with sensor 8.
During test, blank 5 is placed on material carrier platform 7.Pressure mechanism 1 respectively with press down tool heads 2 and be connected with shear tool heads 3, be positioned at the top of material carrier platform 7 and heater coil 4, press down tool heads 2 can independently move under pressure mechanism 1 acts on shear tool heads 3, pressure mechanism 1 is built with multiple sensors 8, and sensor 8 is transferred signals in data collecting instrument 9 by data line.Thermopair 6 is arranged at the middle part of material carrier platform 7, and a part for thermopair 6 is exposed to material carrier platform 7 top, perpendicular to material carrier platform 7.When carrying out test job, it is inner that blank 5 and material carrier platform 7 are positioned at heater coil 4, and thermopair 6 supports blank 5, and blank 5 temperature is sent in data collecting instrument 9.Blank 5 temperature and pressure mechanism are applied to pressure in tool heads and press down speed etc. by sensor transmissions to data collecting instrument 9, and the signal that above various sensor collects is carried out real time record by data collecting instrument 9.
As shown in Figure 2, pressing down tool heads 2 is two half cylindrical structure, has gap between two semicolumns, gap between semicolumn can adjust, shear tool heads 3 is between lower press tool 2 two semicolumns, and its structure is sheet, and the large I of specification is selected according to test request.
Pressure mechanism 1 can adopt hydraulic pressure, air pressure or other form to provide pressure, pressure size and to press down speed adjustable within the specific limits.Heater coil 4 can be induction heating or resistance heated form, and when carrying out test job, it is inner that blank 5 and material carrier platform 7 are positioned at heater coil 4.
In specific implementation process, first get out blank 5 according to test request, be placed on material carrier platform 7 after blank 5 to be tested is worked into certain size, and determine the specification of shear tool heads 3 used.Start heater coil 4 to start to heat blank 5, pressing down tool heads 2 in heating process is pressed on blank 5 by pressure mechanism 1, certain compressive stress is applied to blank 5, along with blank 5 temperature raises gradually, when blank 5 enters after within the scope of semi-solid temperature, pressing down under the effect of tool heads 2 pressure, the thermopair 6 material carrier platform 7 supporting blank 5 inserts blank 5 inside, is sent in data collecting instrument 9 by the temperature signal of inner for blank 5 diverse location.After blank 5 temperature reaches presumptive test temperature, shear tool heads 3 is pressed down in the mode of the pressure of setting speed or setting by pressure mechanism 1, until cut from centre by semi-solid blank 5, so far completes a test process.Press down sensor 8 in process the signals such as pressure, displacement, speed to be sent in data collecting instrument 9 for subsequent analysis.
By conversion shear temperature, shear tool heads specification, shear velocity or shear pressure, repeat above test, the final data obtaining one group of reflection material thixotropic property.Adopt this apparatus and method, accurately can reflect the relation of metal under semisolid condition between the parameter such as deformation temperature, deformation velocity, resistance of deformation, for follow-up thixotropic forming determination thixotropic forming mould structure and technique provide foundation.