adhesion
Enable an AI agent to recognise adhesion between contacting bodies, assess whether their attachment is adequate under stated conditions, and judge whether to establish, preserve, modify or release it.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
Researched by: Codex + Grok
Purpose and description
Enable an AI agent to recognise adhesion between contacting bodies, assess whether their attachment is adequate under stated conditions, and judge whether to establish, preserve, modify or release it.
Adhesion is the interfacial attraction that holds two dissimilar materials or surfaces in contact through intermolecular, chemical, or mechanical interaction, distinct from cohesion within a single material.
It can be Identify the participating surfaces and distinguish demonstrated attachment from contact alone.; Select a separation test appropriate to the intended loading mode and acceptable specimen damage.; Compare preparation or attachment options using results obtained under comparable conditions.; Judge whether available evidence supports continued use under a stated load and environment.; Investigate detachment by locating failure and relating it to preparation, loading and exposure history.; Evaluate release or reattachment options against permitted damage, residue and surface changes..
Distinguishing features
Identify an interface between distinct bodies: rupture wholly within one body is evidence about cohesion and does not by itself establish interfacial adhesion strength.
Determine whether attachment persists when external clamping is removed; resistance present only during clamping may describe friction rather than adhesion.
Check whether separation is prevented by interfacial attachment or solely by a fastener, enclosure or geometric lock.
Distinguish an adhesive substance from an adhesion relationship: possessing or applying adhesive does not demonstrate that attachment formed.
Record the loading mode and conditions of any separation test; a result from one configuration does not establish performance in every configuration.
Scope
+ The bodies, surfaces and contact regions participating in an adhesive attachment
+ Surface preparation, contact history and conditions under which adhesion develops
+ Evidence for the mechanism maintaining attachment across the interface
+ Resistance to separation under specified loading and environmental conditions
+ Loss of attachment, failure location and consequences of intentional release
- Bulk cohesion and mechanical properties of either body except where they constrain interpretation of adhesion
- Adhesive formulation, manufacture and inventory as material or product models
- Complete joining operations, equipment and production workflows
- Attachments maintained solely by fasteners, geometric capture or externally applied clamping
- Frictional resistance without evidence of attachment across the interface
- Social allegiance, adherence to rules and anatomical adhesions requiring distinct contextual models
Characteristics
- Adhering participants and interface
- References to participating bodies, surface regions and any intervening layer Identifies what is attached to what and which interface is being judged.
- Contact configuration
- Direct contact, intervening adhesive layer, multiple interfaces, other specified configuration, unknown Determines which interfaces need evidence and where separation could occur.
- Contact area
- m²; distinguish nominal overlap from measured or estimated actual contact Supports interpretation of attachment extent and area-normalised test results.
- Surface condition
- Recorded cleanliness, moisture, treatment, texture and elapsed time since preparation Allows the agent to connect attachment outcomes to the surfaces actually brought together.
- Proposed attachment mechanism
- Intermolecular interaction, chemical bonding, electrostatic interaction, interdiffusion, capillary contribution, mechanical interlocking contribution, mixed, unresolved Supports mechanism-dependent decisions while keeping hypotheses distinct from observations.
- Attachment state
- Not established, developing, established, partially detached, fully detached, indeterminate Separates preparation and formation from demonstrated attachment and subsequent loss.
- Measured resistance to separation
- Force in N, nominal stress in Pa, peel force per width in N/m, or fracture energy in J/m²; retain method and loading mode Provides a test-specific basis for judging attachment adequacy without treating unlike measurements as interchangeable.
- Exposure and load history
- Linked records of temperature, humidity, fluids, sustained loads, load cycles and exposure durations Places a current assessment within the conditions that may have changed the attachment.
- Observed failure location
- At an identified interface, within adhesive, within a participating body, mixed, unresolved Prevents a joint failure result from being misreported as a direct measurement of interfacial adhesion.
- Adequacy for intended use
- Meets stated criterion, fails stated criterion, insufficient evidence, no criterion specified Connects observations to a particular use rather than assigning an unsupported universal quality rating.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.adhesion
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.
Attachment boundary Establish which bodies and interfaces constitute the adhesion being assessed.
An adhesion judgement is meaningful only when it identifies the attachment relationship and separates it from other restraints.
Participating surfaces
Locate the bodies and contact regions involved.
Interface identity
Record the specific surface pair and any intervening layer without assuming that every interface has equivalent adhesion.
- Which bodies and surface regions are attached, and is contact direct or mediated by an intervening material? definition
- If an intervening layer creates multiple interfaces, which interface does each observation or assessment concern? boundary
Attachment evidence
Distinguish adhesion from contact, friction and external restraint.
Restraint discrimination
Record what supports an adhesion interpretation and what alternative attachment explanations remain.
- What observation demonstrates resistance to separation across the interface rather than contact alone? measurement
- Could clamping, a fastener, geometric capture or another restraint account for the observed attachment? boundary
Surface and formation Describe the surfaces and contact history from which the attachment developed.
The identity of the materials alone does not specify the state of their surfaces or demonstrate successful attachment.
Surface readiness
Capture the condition of each surface when contact occurred.
Precontact surface condition
Record preparation and observed surface condition, distinguishing documented treatment from assumed cleanliness or suitability.
- What cleaning, abrasion, activation, priming or other treatment was applied to each surface, and when? provenance
- What evidence records contamination, moisture, texture or incomplete contact at the intended attachment region? measurement
Attachment development
Track contact conditions and evidence that attachment has developed.
Formation history
Record relevant contact conditions and any waiting, curing or setting requirement without imposing such a requirement on all adhesion.
- Under what contact pressure, temperature, duration and material condition was this attachment formed? provenance
- What evidence establishes readiness for loading, including any applicable curing, setting or dwell requirement? action
Mechanism and contact Connect hypotheses about attachment to evidence about the actual interface.
Mechanism and contact extent help explain behaviour, but neither should be inferred confidently from material names alone.
Mechanism evidence
Separate proposed mechanisms from mechanisms supported for this attachment.
Supported attachment explanation
Record the proposed contributions to attachment, their evidence and competing explanations.
- Which mechanism or combination of mechanisms is proposed to maintain this attachment? definition
- What observation, test or consulted source supports that explanation for these surfaces under these conditions? provenance
Contact extent
Describe how much of the intended interface participates in attachment.
Effective contact region
Distinguish nominal overlap from observed contact and identify gaps or detached regions.
- What are the nominal overlap and observed or estimated actual contact area, and how were they determined? measurement
- Where are voids, edge lifting or uncontacted regions, and which are included in the reported attachment area? boundary
Separation performance Assess resistance to separation in relation to a stated use and test configuration.
An adhesion result needs loading, geometry and acceptance context before an agent can use it to make a decision.
Loading and test
Preserve the conditions that give a separation measurement its meaning.
Test-qualified resistance
Record the measured response with the method, specimen configuration and uncertainty.
- Was resistance measured in peel, normal tension, shear or mixed loading, and at what rate and environmental conditions? measurement
- What result, units, specimen geometry, normalisation basis and uncertainty were reported? measurement
Use acceptance
Relate available evidence to the attachment's intended duty.
Fitness for stated duty
Make adequacy conditional on explicit loads, exposures, duration and acceptance criteria.
- What loads, duration, environments and permissible detachment define acceptable performance for this use? definition
- Does the evidence justify use under those conditions, or is an additional test or use restriction required? action
Detachment and release Track loss of attachment and evaluate intentional separation or reattachment.
An agent must distinguish interfacial loss from damage within a body and understand what release would leave behind.
Loss and failure location
Record changes in attachment and locate the separation path.
Detachment diagnosis
Relate observed detachment to exposure and loading history while preserving uncertainty about cause.
- What change in attached area or separation resistance was observed after sustained load, cycling or environmental exposure? measurement
- Did separation occur at a particular interface, within an adhesive layer, within a body or along a mixed path, and what evidence locates it? measurement
Controlled release
Assess intentional detachment against surface preservation and reuse requirements.
Release and reattachment conditions
Record candidate release actions, their evidential basis and the resulting condition required for reuse.
- Which release method is supported for this attachment within the permitted force, temperature, chemical exposure, damage and residue limits? action
- After release, what inspection, cleaning or replacement is needed before reattachment can be assessed? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Kinds and varieties
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- physical (van der Waals / physisorption) adhesion
- chemical (chemisorption / covalent) adhesion
- mechanical interlocking adhesion
- electrostatic adhesion
- diffusion / interdiffusion adhesion
- cell adhesion (biological)
- tissue adhesion (pathological scar bands)
- contract of adhesion (legal)
- Which of these kinds and varieties hold for the sense of adhesion this model covers, and on what evidence? provenance
Identifiers and schemes
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wikidata - Q193438 - Physical/chemical adhesion as a phenomenon.
- Wikidata - Q245747 - Pathological tissue adhesion (medicine).
- MeSH - D000267 - Tissue Adhesions.
- CAS / adhesive product - manufacturer SKU or UN/CAS of the adhesive, not of adhesion itself - Adhesion as a phenomenon is not a product; bonded assemblies are identified by joint/spec codes.
- Which of these identifiers and schemes hold for the sense of adhesion this model covers, and on what evidence? provenance
Standards and regulation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- ASTM D907 - Standard Terminology of Adhesives (ASTM International)
- ISO 10365 - Adhesives - Designation of main failure patterns (ISO)
- ISO 4587 - Adhesives - Determination of tensile lap-shear strength of rigid-to-rigid bonded assemblies (ISO)
- ASTM D1002 - Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (ASTM)
- ASTM D4541 - Pull-Off Strength of Coatings Using Portable Adhesion Testers (ASTM)
- EN 1939 / related PSA peel methods - pressure-sensitive adhesive peel adhesion (CEN / national bodies)
- FDA 21 CFR (device/tissue adhesives) and EMA rules where medical adhesives or anti-adhesion barriers are regulated as devices or combination products
- Which of these standards and regulation hold for the sense of adhesion this model covers, and on what evidence? provenance
Real-world use
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Structural bonding of metals, composites, glass, and wood in aerospace, automotive, construction, and furniture in place of or with mechanical fasteners.
- Pressure-sensitive tapes, labels, and medical dressings whose function is controlled peel adhesion.
- Coatings, paints, and thin films, where adhesion to the substrate determines service life.
- Cell and platelet adhesion in biology, implant integration, and thrombosis.
- Post-surgical intra-abdominal or pelvic adhesions as a clinical complication.
- Adhesion contracts (standard-form contracts) in consumer and insurance law.
- Which of these real-world use hold for the sense of adhesion this model covers, and on what evidence? provenance
Typical measurements
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- lap-shear strength - 1-40 (structural epoxies often 10-30) - MPa
- peel adhesion (180° or 90°) - 1-20 (commodity PSA tapes often 2-10) - N/25 mm or N/cm
- pull-off (coating) adhesion - 0.5-20 - MPa
- work of adhesion (thermodynamic) - 20-200 (typical organic-solid interfaces; higher if chemisorbed) - mJ/m²
- contact angle (wetting, related) - 0-180 - degree
- tack (probe or loop) - 0.5-20 - N
- Which of these typical measurements hold for the sense of adhesion this model covers, and on what evidence? provenance
Failure modes and hazards
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Adhesive (interfacial) failure: bond separates at the adherend-adhesive interface, often from contamination, poor wetting, or weak boundary layers.
- Cohesive failure in the adhesive or in the substrate, which is not interfacial adhesion failure.
- Environmental degradation: moisture, heat, UV, plasticizer migration, and cyclic stress causing loss of bond strength over time.
- Residual-stress cracking and thermal-expansion mismatch in bonded joints.
- Pathological tissue adhesions causing bowel obstruction, infertility, and chronic pain after surgery.
- Unintended adhesion (sticking, blocking, fouling) of films, medical devices, or process equipment.
- Allergenic or toxic adhesive residues; isocyanate and solvent exposure during bonding.
- In law, adhesion contracts may be unenforceable where terms are unconscionable or not fairly presented.
- Which of these failure modes and hazards hold for the sense of adhesion this model covers, and on what evidence? provenance
Regional variation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- English 'adhesion' covers physics, medicine, and law; many languages split these (e.g. German Adhäsion vs. Verwachsung/Verklebung; French adhérence vs. adhésion for contracts).
- Medical ICD coding and treatment of postoperative adhesions differ by health system.
- Construction adhesive standards and permitted structural uses differ (Eurocodes/EN vs. ASTM/IBC).
- Pressure-sensitive tape peel methods and units (N/25 mm vs. oz/in) still differ between ISO/EN and older ASTM/PSTC North American practice.
- Which of these regional variation hold for the sense of adhesion this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- cohesion - Cohesion is attraction within the same material; adhesion is between dissimilar materials. Failure locus: cohesive failure is inside one phase, adhesive failure is at the interface.
- adsorption - Adsorption is accumulation of molecules at a surface; adhesion is the resulting (or related) mechanical attachment of condensed phases. Adsorption can exist without a usable joint.
- wetting - Wetting is the spreading of a liquid on a solid (contact angle); it is necessary for many adhesive bonds but is not the bond itself.
- friction - Friction is resistance to relative tangential motion; it can include adhesive contributions but is a contact-mechanics force, not a bonded joint.
- tack - Tack is instantaneous stickiness under light pressure and short dwell (especially PSAs); adhesion more generally includes aged, structural, and chemical bonds.
- welding / fusion bonding - Welding joins by melting and coalescence of the substrates; adhesive bonding inserts a third phase (or relies on surface forces) without bulk melting of both adherends.
- mechanical fastening - Fasteners transfer load through discrete mechanical interference; adhesion transfers load across an interface by surface forces and/or an adhesive interlayer.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of adhesion this model covers, and on what evidence? provenance
Sources
- ASTM D907 Standard Terminology of Adhesives - Standard terminology distinguishing adhesion from cohesion and naming adhesive joint types.
- ISO 472 Plastics - Vocabulary - ISO vocabulary for adhesion-related polymer and plastics terms.
- ISO 10365 Adhesives - Designation of main failure patterns - Standard designation of adhesive-joint failure modes (adhesive, cohesive, substrate).
- Adhesion (Q193438) - Wikidata identifier for the physical/chemical phenomenon of adhesion.
What the second pass must settle
- Does the ACT.ACT registry entry intend physical interfacial adhesion, the act of adhering, or another meaning that would change this scope?
- Does an existing Vercy world model already own this concept or part of its attachment relationship?
- Should capillary attachment, electrostatic attachment and microscopic mechanical interlocking be included here or linked to neighbouring attachment models?
- Which test methods and acceptance criteria are appropriate for the material systems and uses this registry entry is expected to cover?
- How should biological surface adhesion and anatomical tissue adhesions be divided between this entry and specialised biological or clinical models?