Application of this unit

This competency applies to technicians who are required to differentiate between products and compounds based on their response to applied stress/strain.

It includes:

crystalline and amorphous polymers

reinforced (fillers or fibres) and filled compounds

crosslinked and uncrosslinked polymers

impact, steady and repeated application

application under different physical and chemical conditions

response of different shapes

applications of this to typical products/situations.

Prerequisites

This unit has no prerequisites.

This describes the essential skills and knowledge and their level required for this unit.

Competence in this unit requires the ability to apply and explain:

classical (ie elastic) stress and strain

classical (ie elastic) Young's modulus and Poisson ratio

stress, compression, shear and torsion

stiffness and bending moments

application of the above for viscoelastic bodies

models of viscoelasticity

creep and relaxation

effects of temperature (above and below the glass transition point)

effects of degradation, eg surface oxidation (such as UV, O3); swelling (such as solvent, chemical)

three dimensional responses to stress

responses to stress cycling, including heat build up

mechanical responses to changing the properties of polymer structures and components

Language, literacy and numeracy requirements

This unit requires the ability to interpret and apply technical information.

Reading is required to the level of reading and applying technical brochures, books and other information.

Numeracy is required to the level of applying technical information and calculating stress/strain and related data, drawing and interpreting graphs.

The Evidence Guide provides advice on assessment and must be read in conjunction with the Performance Criteria, Required Skills and Knowledge, the Range Statement and the Assessment Guidelines for this Training Package.

Overview of assessment

A holistic approach should be taken to the assessment.

Assessors must be satisfied that the person can consistently perform the unit as a whole, as defined by the Elements, Performance Criteria and skills and knowledge.

Critical aspects

It is essential that competence is demonstrated in the knowledge and skills defined in this unit. These may include the ability to:

explain test results in terms which are appropriate to the polymeric material of the sample

apply the results of the analyses to typical applications

identify applications where typical polymer properties are an advantage

distinguish between applications where polymers may be used satisfactorily (although without an inherent advantage) and those where it has an inherent advantage.

Consistent performance should be demonstrated. For example, look to see that:

the model(s) of viscoelasticity can be consistently applied to a range of likely situations

the response to the application of stress in a range of circumstances can be explained

the effect of shape can be predicated and explained for different stress application situations.

Context of assessment

This unit will require an assessment of the underpinning principles and should also include practical analyses as indicated by the elements. Such practical would typically be undertaken in a laboratory, either in an industry workplace or a teaching facility

Competence in this unit may be assessed:

in a teaching facility laboratory

in an industrial laboratory

in a situation where the tests can be done

using suitable simulation and/or a range of case studies/scenarios

through a combination of these techniques.

Method of assessment

In all cases it is expected that practical assessment will be combined with targeted questioning to assess the underpinning knowledge and theoretical assessment will be combined with appropriate practical/simulation or similar assessment. Assessors need to be aware of any cultural issues that may affect responses to questions.

Assessment processes and techniques must be culturally appropriate and appropriate to the oracy, language and literacy capacity of the assessee and the work being performed.

Specific resources for assessment

This section should be read in conjunction with the Range Statement for this unit of competency. Resources required include suitable access to an operating plant or equipment that allows for appropriate and realistic simulation. A bank of case studies/scenarios and questions will also be required to the extent that they form part of the assessment method. Questioning may take place either in the workplace, or in an adjacent, quiet facility such as an office or lunchroom. No other special resources are required.

Access must be provided to appropriate learning and/or assessment support when required. Where applicable, physical resources should include equipment modified for people with disabilities.

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording in the Performance Criteria is detailed below. Add any essential operating conditions that may be present with training and assessment depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts.

Where reference is made to industry codes of practice and/or Australian/international standards, the latest version must be used.

Context

This competency applies to technicians who are required to analyse the mechanical/ physical responses of polymer structures and components. These may include:

large structural beams,

small mechanical components,

damping products such as bridge or acoustic bearings

other items where the mechanical/physical properties are important.

It includes a wide range of polymer compounds including:

crystalline and amorphous polymers

reinforced (fillers or fibres) and filled compounds

crosslinked and uncrosslinked polymers.

However, the properties of these polymers is not the prime focus of this unit.

Procedures

All operations are performed in accordance with procedures.

Procedures means all relevant workplace procedures, work instructions, temporary instructions and relevant industry and government codes and standards. ASNZ/ISO standards for mechanical/physical testing of polymers will be relevant here and appropriate standards should be followed.

Tools and equipment

This competency includes use of equipment and tools such as:

stress/strain testers

impact testers

cycling testers

environmental aging equipment

basic length/thickness measuring equipment.

Hazards

Typical hazards include:

stored energy (eg in stressed test samples

test preparation equipment

conditions and materials used for causing sample degradation.

Not applicable.

This unit contains employability skills.

Not applicable.