Quantifying Wet Spinning Limits for Low Cohesion Bast Fiber Slivers
Low cohesion flax slivers collapse under high draft ratios, requiring reduced trough temperatures, higher roving twist, and tight ratch settings to hold count.
Tensile Stress Strain Curve
Tensile Metric
Flax bast fibres undergo progressive mechanical loading on a specialized frame during spinning preparation to establish the tensile stress strain curve. Force values divided by cross sectional area yield stress parameters while elongation percentages form the strain axis on the resulting graph. Commercial testing laboratories record these curves during raw material grading to separate fine spinning lots from coarser weaving supplies.
Internal mill specifications govern routine quality control whereas binding purchase contracts demand external laboratory verification certificates. A tensile stress strain curve evaluates mechanical integrity up to the point of rupture.
Elastic Region
Hooke dictates linear proportionality between initial stress application and subsequent deformation inside this initial sector. Cellulose microfibrils within the plant cell wall align along the axis of applied tension during this phase. Permanent structural alteration remains absent until stress surpasses the proportional limit.
Exceeding this boundary initiates microscopic dislocation within the cellular matrix.
Plastic Deformation
Permanent elongation accumulates rapidly as loading continues beyond the yield point toward final rupture. Molecular chains slide past neighboring structures while internal friction generates measurable thermal energy. Failure occurs abruptly once ultimate tensile strength is reached and microfractures coalesce across the specimen width.
Contract specifications penalize lots displaying premature yielding because processing machinery demands predictable elasticity during high speed drafting operations.