© 2016 Slade Gardner Advanced Manufacturing and Materials, LLC – All Rights Reserved

Panel II: Process Models

Slade Gardner, PhD - President

Slade Gardner Advanced Manufacturing and Materials

June 9, 2016
© 2016 Slade Gardner Advanced Manufacturing and Materials, LLC – All Rights Reserved

Panel II: Process Models

 Panel II: Process Models

 This panel includes: feedback and feedforward models, thermal modeling, 

constitutive models, molecular modeling, etc.

 Panelists: Slade Gardner (Slade Gardner Advanced Manufacturing and 

Materials), Peter Olmsted (Georgetown University), and David Roberson 

(University of Texas - El Paso)

 Moderator: Kalman Migler (NIST)

 Questions: What types of models are required to achieve fundamental 

understanding of AM processes; to enable real-time control? What types of 

input data are required?

2
© 2016 Slade Gardner Advanced Manufacturing and Materials, LLC – All Rights Reserved

Purpose for Process Models

 Commercialization & adoption of polymers-based additive manufacturing

 Quality Manufacturing - Achieve design intent through processing

 Design intent is evolving through generative optimization methods

 Unique designs require agnostic, reliable and flexible verification – fundamentals

 Quality Control – Production according to established metrics

 Uniformity and consistency throughout part

 Part to part consistency

 Quality Assurance – Defect prevention / confidence: requirements will be fulfilled

 Fit for purpose - product suitable for intended purpose

 Right first time - mistakes eliminated

 Management of raw materials, equipment and components, processes related to 

production and verification processes

 Certification data according to manufacturing quality metrics

 Standards for Measurement, Verification and Models

3
© 2016 Slade Gardner Advanced Manufacturing and Materials, LLC – All Rights Reserved

Generalized Perspective

Product 

(Quality)

Process 

(Data) Design MFG

4

 Feed Forward – model predictions to guide process

 Physics based modeling 

 Process analysis/simulation (multi-scale)

 Feed Back – measurement of process variables to guide control input

 Discrete, Batch and Continuous

 PLC  multi note sensor network feeding artificial intelligent processor 
© 2016 Slade Gardner Advanced Manufacturing and Materials, LLC – All Rights Reserved

Process Parameters

 Quality is goal

 Dimensional control

 Flow and stability

 Rheology

 Thermal History

 Adhesion (∆Tg)

 Bonding / Interdiffusion

 Chemistry / Composition

 Sensors and Measurement

 Response Time

 Practical Utility of Data 

 Melt

 (II) temperature and flow rate

 (I) motion control

 Extrudate

 (II) interaction with melt

 (I) temperature history 

 Substrate

 (III) preparation for interdiffusion

 (IV) sensing and measurement

5

substrate

extrudate

melt

I II III IV
© 2016 Slade Gardner Advanced Manufacturing and Materials, LLC 

– All Rights Reserved

Complications to consider

6

 Size / Scale  Complexity  Path and Design  Starts / Stops  Turns and Bends  Trapped Geometry  Dimensions (integer thickness)  Surface Features  Surface Finish  Distortion / Thermal Balance  Multi Material  Integrated Components  Atmosphere / Environment