Materials Selection and Property Envelopes

Seminar Overview

Most material failures are selection failures — the part was specified from a datasheet number that was true and irrelevant. This seminar teaches material selection the way it must actually be done: by building and defending property envelopes, the band of conditions (temperature, load, chemical exposure, moisture, time) inside which a specific resin — at a specific filler loading, in a specific conditioned state — actually performs. The course is grounded in two sources that rarely appear together: the resin-producer primary literature from the design-guides corpus (Covestro, BASF Ultramid, DuPont Delrin/Crastin/Zytel/Minlon, Victrex PEEK, BPF guidance, plus the Parker O-Ring Handbook and Loctite Design Guide for Bonding Plastics where elastomers and adhesives meet material choice), and a structured corpus of 900+ field-recorded plastic-engineering entries — 336 PRINCIPLE records, 118 MATERIAL ENVELOPE records, and 132 DECISION CRITERION records captured across four decades of consulting practice.

The field records are the course's spine because they carry what datasheets omit: real numbers and real outcomes. Glass-filled PP losing weld-line strength from 8,500 psi down to 1,600–3,200 psi at the knit line. Shrinkage running 0.030 in/in where the datasheet said otherwise. Dyne levels of 29, 31, and 42 and what each means for printing, painting, and bonding. Tolerances held at ±0.0005 inch — and which ones held and which didn't. CLTE behavior across filled and unfilled families. Every module pairs the handbook method with these recorded envelopes, so the class practices selection against materials as they behave in service, not as they behave in a tensile bar.

The differentiator: this seminar is taught from PRIMARY SOURCE material — producer design guides and documented engineering records — not vendor slide decks. You leave with a repeatable screening method you can defend in a design review or a supplier negotiation.

Ideal Learner

• Product and design engineers who specify thermoplastics and thermosets for structural and functional parts
• Materials engineers and applications engineers at resin producers, compounders, and distributors
• Supplier-quality and SQA engineers validating material substitutions and "equivalent" resin swaps
• Design-review leads and program engineers who must approve material choices and own their consequences
• Industry segments: automotive OEM/Tier 1, medical devices, consumer products, electrical/electronics, industrial equipment

Learning Objectives

• Distinguish thermoplastic from thermoset behavior at the processing and in-service level and justify the family choice for an application
• Explain crystalline, amorphous, and liquid-crystalline polymer structure — and how structure drives shrinkage, chemical resistance, dimensional stability, and failure mode
• Construct a property envelope for a candidate resin across thermal, mechanical, and chemical dimensions, using time-dependent (creep, stress relaxation) limits rather than datasheet spot values
• Predict the property and processing consequences of fillers, reinforcements (glass, mineral), and additive packages — including anisotropy and weld-line knockdowns
• Apply moisture and shrinkage kinetics (nylon conditioning, post-mold shrinkage, CLTE-driven dimensional change) to tolerance and fit decisions
• Run a documented material screening against an OEM-type specification, producing a defensible selection memo with envelope evidence
• Recognize the classic envelope failures: glass-filled weld-line strength loss, unconditioned nylon assumptions, room-temperature datasheet values applied at operating temperature

Consulting Sessions

Seminar attendees can sign up for individual consulting sessions with the instructor. Sessions are free for registered attendees, first-come first-served — sign up when registering by calling 248-539-0473 or during the seminar.