Materials, processes and models.

Tooling-driven densification of powder in a die using punch loading, including unloading and ejection behaviour.

DTVL supports simulation of powder compaction for pharmaceutical powders, ceramic powders, metal powders / powder metallurgy and other compactable particulate materials exhibiting pressure-driven densification, where the constitutive model and parameters are suitable. The workflow can represent evolving nonlinear elastic behaviour, including stiffness and Poisson’s ratio dependence on relative density and pressure, together with configurable tooling, geometry and friction conditions.

Mechanical analysis can use an elastic-only response or supported plasticity such as Drucker–Prager Cap. Optional thermal coupling can investigate temperature evolution and thermo-mechanical behaviour during compaction, where supported by the selected workflow and material model.

The modelling approach builds on doctoral constitutive-model research at the University of Leicester under the supervision of Prof. Csaba Sinka.

Constant friction

μ = constant

State-dependent friction

μ = f(p, RD)

Static → kinetic friction

μ_static → μ_kinetic = f(p)after sliding begins

Pressure-driven densification of powder bodies under distributed surface pressure without explicit punch-and-die pressing.

Compaction can also be represented under approximately hydrostatic or isostatic pressure loading, where the component is densified through pressure acting around its external surface rather than predominantly through rigid punch-and-die loading.

Cold Isostatic Pressing and hydrostatic loading have a frontend configuration prototype; solver support and application-specific suitability require implementation and validation. HIP is a separate geometry prototype involving pressure, elevated temperature and time-dependent densification; full numerical execution remains under development.

Continuum simulation of powder densification between counter-rotating rolls using a Lagrangian finite-element formulation.

The current DTVL workflow uses a finite powder domain with defined feed geometry, roll-gap conditions, material behaviour and powder–roll interaction. The computational mesh follows the deforming powder. Very large material transport through the roll gap may eventually produce excessive mesh distortion; practical deformation limits depend on geometry, material behaviour, contact conditions and mesh resolution.

Advanced analysis of unloading, punch withdrawal and ejection from a saved compacted-state checkpoint. The intended workflow investigates springback, residual stresses, failure initiation, progressive material degradation and, where supported, element deletion without repeating the preceding compaction simulation.

Alternative integrity and damage formulations can be applied to the same compacted state for comparative studies. Die Compaction → saved peak-compaction checkpoint → Post-Compaction Integrity & Damage Analysis. The source job may have completed later stages; the branch starts from the chosen saved checkpoint.

Current controls are prototype configuration only. State transfer, damage initiation and evolution, degradation, regularisation and element deletion are under development and validation. Visible simulation results alone do not contain the complete saved process state.

The underlying approach builds on experimental and numerical investigation of capping during unloading and ejection in pharmaceutical tablet manufacture undertaken during doctoral research at the University of Leicester. Capping is a demonstrated application rather than the full scope of this capability.

Crack prediction requires an appropriately validated damage model; critical stress or localisation alone does not guarantee prediction of cracking.

Thermally driven densification, shrinkage and shape evolution under internal sintering stresses and applicable mechanical constraints.

Model densification, shrinkage and deformation during sintering.

Where supported, external loads, gravity, applied pressure and fixture/support reactions can influence deformation. Mechanical deformation can be driven by internal sintering stress as well as external loads, gravity, supports or constraints. Viscoplastic is a mechanical response class; external loading is optional. A prescribed temperature history does not necessarily involve a solved thermal field. Coupling availability depends on the selected workflow and material model.

Sequential simulation of die compaction, green-body state transfer and subsequent sintering.

Coupling availability depends on the selected workflow and material model. This sequential workflow uses die compaction as its first stage. Initial powder → Die compaction → Unloading/ejection → Green compact → Heating → Sintering. Subsequent sintering can inherit final geometry, relative density and compatible stress, plastic/state and history variables where supported. Prototype configuration records transfer requests; it does not generate or transfer computed solver state.

Standard configurable workflows cover supported process families. Bespoke coupled workflows can be developed for customer-defined component geometry, internal and external features, tooling, pressure histories, thermal cycles, supports, contact conditions and other application-specific requirements.

Customer-specific coupled models can be deployed only within the requesting customer’s private DTVL environment.

Mixture-rule-based prediction for mechanically compacted multi-component powder systems

DTVL can support formulation design for multi-component powder systems undergoing mechanical compaction. Component-level compaction behaviour is combined using mixture rules to estimate formulation response across composition and processing conditions.

Potential applications include pharmaceutical powders, ceramic powder mixtures, metallic powder mixtures and other compactable particulate systems. The methodology has been demonstrated for pharmaceutical tablet formulation; application to other compacted powder systems requires suitable component-level data and validation. Predictive accuracy depends on whether the mixture rule adequately represents interactions between constituents.

Depending on the application, a feasible design window can be based on prescribed mechanical, compaction or manufacturing criteria, including strength, ejection behaviour, relative density, compaction-pressure limits and other validated criteria.

DTVL builds on the Successful Formulation Window methodology developed during doctoral research at the University of Leicester under the supervision of Prof. Csaba Sinka, with industrial collaboration from AstraZeneca. This academic origin is distinct from DTVL platform development.

The current methodology addresses mechanical and manufacturability criteria. Additional pharmaceutical quality attributes require separate models and validation.

Thermal and thermomechanical simulation of products during kiln and furnace processing, including transient heating, thermal gradients, mechanical restraint, support interaction and, where applicable, sintering-driven densification and distortion.

Analysis scope can range from thermal-only heating studies to coupled product sintering with supports and thermal contact. Supported physics are Mechanical [M] and Thermal [T], with Elastic [E], Plastic [P] and Viscoplastic [VP] material responses where applicable. Supported capabilities do not require every response to be active.

Configuration prototype for silo/hopper stress, wall loads, gravity settling, outlet opening and incipient or early discharge. Numerical execution is not connected.

The configuration records cohesion, internal friction, wall friction, density, compressibility and constitutive parameters for future assessment of stress and wall loading. Arching and stagnant-region predictions are planned and require validation.

Full silo emptying, die filling and large material transport remain future large-deformation capabilities.

Guided finite-element simulation of standard mechanical characterisation tests using predefined specimen, loading, support and contact templates. The workflow reduces the need for manual model construction while retaining control over specimen dimensions, applied load or displacement, support geometry, friction and material behaviour.

Mechanical [M] is the initial physics scope. Elastic [E], Plastic [P] and compatible Viscoplastic [VP] responses are selected according to material formulation rather than imposed by test type. Thermal test variants are planned.