Knowledge
The IET Knowledge Base
Every material has a signature. These guides teach you to read it, from first principles to the standards, methods, and comparisons that put it to work.
29 guides across 5 topics
Fundamentals
What resonance is, and why a free-vibrating specimen reveals elastic properties.
What is Impulse Excitation Technique (IET)?
A complete guide to the non-destructive method for measuring elastic properties of materials, covering the physics, the practice, and the applications.
Read guide →Acoustic Resonance Testing Explained
Acoustic resonance testing measures material properties by analyzing vibration frequencies after a mechanical tap. The standardized form is impulse excitation technique (IET), governed by ASTM E1876.
Read guide →AI-Powered Quality Control with Impulse Excitation
How artificial intelligence and machine learning enhance impulse excitation testing for inline quality control: automated defect classification, adaptive thresholds, and predictive sorting.
Read guide →Why Resonance Frequencies Shift During Testing
Why resonance peaks shift during impulse excitation testing: stiffness, temperature, defects, and damping effects explained.
Read guide →Monitoring Sintering with Impulse Excitation
How impulse excitation tracks densification non-destructively: elastic modulus and damping changes through sintering stages.
Read guide →How Vibrations Reveal Young's Modulus
The physics behind impulse excitation: how resonant frequencies reveal Young's modulus through f proportional to sqrt(E/rho).
Read guide →How Impulses Reveal Material Quality and Strength
What a single tap reveals about material quality: how elastic modulus and damping correlate with strength and detect hidden defects.
Read guide →Grinding Wheels Made It Clear: Why Impulse Excitation Works
How grinding wheel testing in 1960s Belgium launched impulse excitation technique, from subjective ring tests to quantitative E-modulus grading.
Read guide →Standards
ASTM E1876, C1259 and the test methods that make results comparable worldwide.
ASTM E1876: The Standard for Impulse Excitation Testing
Practical guide to ASTM E1876, the standard test method for measuring dynamic Young's modulus, shear modulus, and Poisson's ratio by impulse excitation. Specimen requirements, procedure, calculations, and compliance.
Read guide →Young's Modulus of Ceramic Materials — An Intercomparison of Methods
EC-sponsored evaluation of four methods for measuring elastic moduli of advanced technical ceramics per CEN ENV 843-2. Impulse excitation, sonic resonance, ultrasonic pulse, and quasi-static flexure compared for repeatability and reproducibility.
Read guide →Methods
How to run the measurement, prepare specimens, and turn frequencies into moduli.
How to Measure Elastic Properties with Impulse Excitation
Step-by-step guide to measuring Young's modulus, shear modulus, and Poisson's ratio for rectangular bars, cylinders, and discs.
Read guide →How to Choose IET Equipment: A Buyer's Guide
What to look for when selecting impulse excitation testing equipment for your lab or production line. Frequency range, resolution, standards compliance, and automation options compared.
Read guide →Non-Destructive Porosity Measurement with IET
Measure porosity non-destructively using impulse excitation technique. Detect gas porosity, lack-of-fusion, and incomplete sintering through resonance frequency and damping analysis.
Read guide →Impulse Excitation Testing for Ceramics and Glass
How impulse excitation characterizes ceramics, glass, and refractories: elastic modulus, damping, and thermal shock detection per ASTM C1259.
Read guide →Impulse Excitation Testing for Metals and Alloys
How impulse excitation characterizes steels, cast irons, superalloys, and powder metallurgy parts: foundry QC to fatigue testing per ASTM E1876.
Read guide →Concrete Testing with Impulse Excitation
How impulse excitation measures dynamic modulus and damping in concrete per ASTM C215: hydration monitoring, freeze-thaw, and fire damage.
Read guide →Impulse Excitation for Precision Components
Impulse excitation quality assurance for dental implants, turbine parts, bearings, and precision components. Sub-ppm accuracy per ASTM E1876.
Read guide →Sintering Quality Control by Impulse Excitation
How impulse excitation detects incomplete sintering, porosity, and microcracking in ceramics, PM, and AM parts. 1,000+ parts/hour.
Read guide →How to Detect Defects in Additively Manufactured Parts
Impulse excitation catches porosity, lack-of-fusion, and microstructural anomalies in AM parts. Faster and cheaper than CT scanning.
Read guide →Impulse Excitation for Aerospace Materials
How impulse excitation addresses aerospace quality demands: AM superalloy fatigue, thermal barrier coatings, and radome ceramics testing.
Read guide →Concrete Stiffness and Damping by Impulse Excitation
Dynamic modulus and damping measured by impulse excitation reveal microcracking, alkali-silica reaction, and freeze-thaw damage per ASTM C215.
Read guide →Impulse Excitation Testing for Glass and Lenses
Impulse excitation measures elastic modulus and damping in optical glass per ASTM C623, detecting annealing stress and compositional variation.
Read guide →De-Risking Additive Manufacturing with NDT
NDT methods reduce AM production risk by catching porosity, lack-of-fusion, and residual stress. Impulse excitation screens parts at under $1 each.
Read guide →Brake Pad Testing with Impulse Excitation
How impulse excitation measures resonant frequency and damping per SAE J2598 for 100% quality control of brake pads and friction materials.
Read guide →Grinding Wheel Testing with Impulse Excitation
How impulse excitation grades grinding wheels by elastic modulus, detects cracks, and enables 100% non-destructive inspection per EN 12413.
Read guide →Comparisons
How IET sits against ultrasonic, static, and other non-destructive methods.
Impulse Excitation vs Ultrasonic vs X-Ray CT
Comparing impulse excitation, ultrasonic, X-ray CT, and eddy current testing: cost, throughput, sensitivity, and best applications.
Read guide →Impulse Excitation vs Destructive Testing
How impulse excitation correlates with tensile strength, hardness, and fracture data, and where destructive testing remains essential.
Read guide →Impulse Excitation vs Process Compensated Resonance Testing
Both sort parts by resonance, but they read different signals. How GrindoSonic IET's damping analysis adds an axis that frequency-only PCRT does not capture, and when each one fits.
Read guide →Research
Deeper studies and applied investigations across material families.