Bending moments induced by minor non-parallelism between the upper and lower bonding blocks cause asymmetric edge peeling.
Integrate fully articulating dual-axis universal joints on both the top and bottom pull-rods to isolate axial tension.
Cure the bonded block assembly under a uniform dead-weight load to ensure a perfectly flat, parallel adhesive layer.
Cure the bonded block assembly under a uniform dead-weight load to ensure a perfectly flat, parallel adhesive layer.
Eliminating eccentric bending moments ensures uniform out-of-plane tensile stress distribution across the entire sandwich cross-section.
Verify that failure occurs purely within the core or core-to-skin interface; any block-adhesive failure above 10% requires a retest.
Using rigid, non-articulating pull rods which force severe bending and cause the sample to peel early from one edge.
Typical testing system controllers rely on 24-bit resolution. Under high-accuracy flexural analysis, this creates a data phenomenon called **”stair-stepping”** or quantization error. When trying to track minor micro-deflection in rigid polymers, 24-bit electronic circuits suffer from resolution limits, dropping critical transition points during initial load curves.
Newton Characterization™ architecture utilizes a 32-bit analog-to-digital processor converter. This increases measurement fidelity by a factor of 256x, outputting 4.29 billion discrete signal thresholds. Electrical chatter is actively muted under a dedicated 100,000:1 Signal-to-Noise Ratio (SNR).
Comparing standard 24-bit quantization with Newton™ 32-bit resolution
Observe the stepped resolution blocks in the legacy 24-bit curve (Red) versus the absolute **analog-smooth response curve** captured by Newton™ 32-bit architectures (Green). This fidelity is what prevents mechanical data variance during modulus evaluation.
Expert Engineering Commentary
Core Problem Identification
Edge failures or early debonding at the metal block interface, rendering the structural core test metrics completely invalid.
Root Cause Analysis
Non-uniform adhesive thickness or eccentric loading profiles focusing localized stress concentrations on the coupon perimeter.
Hardware Specific Solutions
Self-aligning gimbaled or dual-universal-joint pull fixtures fitted with hard-anodized high-strength aluminum bonding blocks.