Abstract
The micro hot-embossing process is an efficient and low-cost manufacturing process that can produce components with complex geometries in a wide variety of materials. The physical behaviour of the material needs to be investigated to achieve optimisation of the process. Many experimental results have been presented in the literature; however, modelling of the material properties and simulations of the process to improve the microreplication quality are still lacking. The principal scientific challenge in the numerical simulation is to provide an efficient material behaviour law to describe the deformation of the material during the process. The physical constitutive behaviour law of polymer plates in the hot-embossing process can be treated as viscoelastic or viscoplastic, depending on the various process boundary conditions. This study mainly concerns the identification of a physical constitutive behaviour law for an amorphous polymer poly (methyl methacrylate) (PMMA), which is used in hot-embossing processes at the microscale. Uniaxial compression tests were carried out under various temperature conditions slightly above the glass transition temperature (Tg) of the polymer, and the viscoplastic behaviour of the polymer was characterised. In the present study, the fabrication of a complex microfluidic device is treated as a case study, focusing on the filling stage of the process. Modelling in numerical software using the implemented polymer behaviour model was realised, and the influence of different processing and material parameters on the filling efficiency was investigated at the microscale in two different zones (channel and reservoir). Specific related microreplications in the processing temperature range from Tg + 20 °C to Tg + 40 °C with different material parameters were also studied and compared. The results of the simulation were in good agreement with the experimental results in terms of replication for the PMMA amorphous thermoplastic polymer compared at different microscales and in different zones, confirming the efficiency of the proposed approach with different comparisons in 2D and 3D cases. Moreover, the models can be used when similar behaviours are observed in amorphous thermoplastics and extended to other micro hot-embossing components.
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References
Abaqus User’s Manual (2016) Dassault Systèmes, Providence, RI
Andersen TE, Andersen AJ, Petersen RS, Nielsen LH, Keller SS (2018) Drug loaded biodegradable polymer microneedles fabricated by hot embossing. Microelectron Eng 195:57–61
Bardenhagen SG, Stout MG, Gray GT (1997) Three-dimensional, finite deformation, viscoplastic constitutive models for polymeric materials. Mech Mater 25:235–253
Becker H, Heim U (2000) Hot embossing as a method for the fabrication of polymer high aspect ratio structures. Sensor Actuat A-Phys 83:130–135
Cheng G, Sahli M, Gelin J-C, Barriere T (2016) Physical modelling, numerical simulation and experimental investigation of microfluidic devices with amorphous thermoplastic polymers using a hot embossing process. J Mater Process Technol 229:36–53
Dreistadt C, Bonnet A-S, Chevrier P, Lipinski P (2009) Experimental study of the polycarbonate behaviour during complex loadings and comparison with the Boyce, Parks and Argon model predictions. Mater Design 30:3126–3140
Drozdov AD (2001) A model for the viscoelastic and viscoplastic responses of glassy polymers. Int J Solids Struct 38:8285–8304
Esmaeilpour R, Kim H, Park T, Pourboghrat F, Mohammed B (2017) Comparison of 3D yield functions for finite element simulation of single point incremental forming (SPIF) of aluminum 7075. Int J Mech Sci 133:544–554
Esmaeilpour R, Kim H, Park T, Pourboghrat F, Xu Z, Mohammed B, Abu-Farha F (2018) Calibration of Barlat Yld2004-18P yield function using CPFEM and 3D RVE for the simulation of single point incremental forming (SPIF) of 7075-O aluminum sheet. Int J Mech Sci 145:24–41
Federico CE, Bouvard JL, Combeaud C, Billon N (2018) Large strain/time dependent mechanical behaviour of PMMAs of different chain architectures. Application of time-temperature superposition principle. Polymer 139:177–187
Frank GJ, Brockman RA (2001) A viscoelastic-viscoplastic constitutive model for glassy polymers. Int J Solids Struct 38:5149–5164
Gudimetla MR, Doghri I (2017) A finite strain thermodynamically-based constitutive framework coupling viscoelasticity and viscoplasticity with application to glassy polymers. Int J Plast 98:197–216
Holmes DW, Loughran JG (2008) Theoretical aspects of the testing of elasto-viscoelastic–viscoplastic materials. Polym Test 27:189–203
Holopainen S, Barriere T (2018) Modeling of mechanical behavior of amorphous solids undergoing fatigue loadings, with application to polymers. Comput Struct 199:57–73
Hu W, Guo H, Chen Y, Xie R, Jing H, He P (2016) Experimental investigation and modeling of the rate-dependent deformation behavior of PMMA at different temperatures. Eur Polym J 85:313–323
Kim SH, Chung JW, Kang TJ, Kwak S-Y, Suzuki T (2007) Determination of the glass transition temperature of polymer/layered silicate nanocomposites from positron annihilation lifetime measurements. Polymer 48:4271–4277
Kim J-S, Muliana AH (2010) A combined viscoelastic-viscoplastic behavior of particle reinforced composites. Int J Solids Struct 47:580–594
Kurita T, Ogura I, Ashida K (2018) Proposal of laser assisted hot embossing technology for glass. J Mater Process Technol 254:248–253
Lee TY, Han K, Barrett DO, Park S, Soper SA, Murphy MC (2018) Accurate, predictable, repeatable micro-assembly technology for polymer, microfluidic modules, Sens. Actuators, B 254:1249–1258
Liang C, Meng F, Li J, Liu C (2018) Using CO2-laser bugle for ultrasonic bonding of thermoplastic microfluidic devices. J Mater Process Technol 252:25–33
Mareau C, Favier V, Berveiller M (2009) Micromechanical modeling coupling time-independent and time-dependent behaviors for heterogeneous materials. Int J Solids Struct 46:223–237
Mathur A, Roy SS, Tweedie M, Mukhopadhyay S, Mitra SK, McLaughlin JA (2009) Characterisation of PMMA microfluidic channels and devices fabricated by hot embossing and sealed by direct bonding. Curr Appl Phys 9:1199–1202
Oliveira J, Correia V, Castro H, Martins P, Lanceros-Mendez S (2018) Polymer-based smart materials by printing technologies: improving application and integration. Addit Manuf 21:269–283
Srivastava V, Chester SA, Ames NM, Anand L (2010) A thermo-mechanically-coupled large-deformation theory for amorphous polymers in a temperature range which spans their glass transition. Int J Plast 26:1138–1182
Voyiadjis GZ, Shojaei A, Li GQ (2012) A generalized coupled viscoplastic-viscodamage-viscohealing theory for glassy polymers. Int J Plast 28:21–45
Wang J, Yi P, Deng Y, Peng L, Lai X, Ni J (2017) Recovery behavior of thermoplastic polymers in micro hot embossing process. J Mater Process Technol 243:205–216
Worgull M, Heckele M (2004) New aspects of simulation in hot embossing. Microsyst Technol 10:432–437
Worgull M (2009) Hot Embossing Tools. In: Hot embossing: theory and Technology of Microreplication. Elsevier Inc, Burlington
Xiao R, Sun HG, Chen W (2017) A finite deformation fractional viscoplastic model for the glass transition behavior of amorphous polymers. Int J Nonlinear Mech 93:7–14
Yu C, Kang G, Chen K, Lu F (2017) A thermo-mechanically coupled nonlinear viscoelastic–viscoplastic cyclic constitutive model for polymeric materials. Mech Mater 105:1–15
Zairi F, Nait-Abdelaziz M, Woznica K, Gloaguen J-M (2005) Constitutive equations for the viscoplastic-damage behaviour of a rubber-modified polymer. Eur J Mech A-Solid 24:169–182
Zhang N, Srivastava AP, Browne DJ, Gilchrist MD (2016) Performance of nickel and bulk metallic glass as tool inserts for the microinjection molding of polymeric microfluidic devices. J Mater Process Technol 231:288–300
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Cheng, G., Barriere, T. Effect of viscoplasticity on microfluidic cavity filling efficiency of a thermoplastic polymer in hot-embossing process. Int J Adv Manuf Technol 103, 549–565 (2019). https://doi.org/10.1007/s00170-019-03447-1
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DOI: https://doi.org/10.1007/s00170-019-03447-1