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Destructive testing is a type of evaluation that determines how a component will behave under pressure until it fails. Non-destructive testing also assesses an object’s behavior but does so without permanently damaging it. While both methods deliver valuable information, non-destructive tests are emerging as a more efficient means of analyzing materials.

What Is Destructive Testing?

Destructive tests often detect failures using high-speed cameras that record continuously until they identify the malfunction. Sound detectors or stress gauges transmit a signal to set the camera into motion. After the failure, the camera will stop recording, and you can review the images in slow motion to determine what happened before, during and after the destructive event.

In most cases, destructive testing methods test components before mass production begins. Destructive tests give original equipment manufacturers (OEMs) an idea of their products’ limits to administer the necessary machine maintenance and operating recommendations.

Because destructive tests result in irreversible damage, the tested item and its parts cannot be reused in regular operation after enduring destructive testing. Though these items become damaged through destructive testing without the chance of recovery, this method still has legitimate use cases.

Machines have physical and chemical properties that aren’t appropriate for all working conditions. For example, metals that are prone to corrosion are not well-suited for use in humid environments. Destructive testing points out these incompatibilities and potential drawbacks to prevent them from failing for end users. In some industries, this test method is a regulatory requirement.

Destructive Testing Methods

There are various types of destructive testing that organizations use to evaluate material quality and performance. Each destructive testing method has specific case uses and follows particular standards and practices.

Though there are several types of destructive testing, the following tests are some of the most commonly used.

Corrosion Testing

Corrosion testing is used to evaluate the effectiveness of corrosion-resistance measures to prevent metal components from rusting, tarnishing and pitting in diverse environments, including freshwater and seawater settings. According to the American Society for Testing and Materials (ASTM), destructive corrosion tests, behavior and extent of resistance to various types of corrosion.

Fracture and Mechanical Testing

Fracture mechanical testing methods examine the effects of flaws on a material’s load-bearing capacity and toughness.

Fracture and mechanical testing methods include various destructive tests, including:

Tension tests
Charpy impact tests
Peel tests
Crush testing
Bend tests
Pellini drop weight testing
Pressure testing
Fracture testing

These types of destructive testing are used under different temperatures and strain rates to evaluate fracture toughness, static behavior, strength and cyclic behavior in pressure performance, creep and seawater environments. The results of these destructive tests can help assess and validate material integrity.

Aggressive Environmental Testing

This destructive test type uses fracture and fatigue testing to measure a machine’s effectiveness in corrosive environments, such as sour and sweet conditions, under various pressures and temperatures. Through aggressive environmental testing, users test materials based on the characteristics of their intended operating settings.

For example, when testing building materials for a beach house, you’d use aggressive environmental testing to ensure that it could withstand the humidity, high winds and salinity typical of coastal areas.

Fatigue Testing

Fatigue testing is a type of mechanical destructive test used to generate data on crack growth and fatigue life, identify areas susceptible to fatigue, or demonstrate structural safety. These evaluations determine a welded joint’s ability to endure cyclic fatigue loading conditions in either air or seawater environments.

Fatigue testing is often used on components for full-size test articles like aircraft and automobiles. It’s also used for fatigue crack growth testing on base metals, heat-affected zones and welds.

Residual Stress Measurement

Residual stress measurement determines whether a material can withstand extreme load conditions throughout its intended service life. These destructive tests allow engineers and designers to assess crucial component flaws and generate critical assessments.

Tensile Testing

Tensile testing, also known as elongation testing, is the process of applying controlled forces to a test material until it fails. Through this destructive testing method, the specimen is elongated or compressed based on the applicable measurement characteristics to determine the material’s strength. With these results, you can discover which materials will perform well under excessive amounts of force.

Properties you can assess through tensile testing include breaking strength, reduction, ultimate tensile strength and maximum elongation.

Destructive Testing Applications

Destructive testing methods have long been a reliable source for testing specimen failure. Numerous industries utilize the destructive testing of materials in all of the following applications:

Earthquake testing: Destructive tests can evaluate how large structures like buildings will perform during earthquake events. These evaluations often take place on a shake table, which produces similar movement as an earthquake.
Software testing: You can use destructing testing to test a software’s robustness and stability. By causing the software to fail, you can establish range limits accordingly to ensure reliable operation.
Automotive testing: Crash tests are a type of destructive testing designed to ensure safe vehicle design standards, such as crash compatibility and crashworthiness, by subjecting an automobile to crash conditions.
Aircraft testing: It is standard to use destructive testing to evaluate passenger and military aircraft production models by loading components until they fail.
Fabrication validation: Manufacturing validation is the process of ensuring that based on its service conditions and time between failures.
Materials characterization: Destructive testing methods help measure a material’s properties and structure in the materials science field. They give valuable insights into why certain substances exhibit different behaviors and characteristics.
Failure investigation: Failure investigation through destructive testing is used to improve asset performance by identifying the causes of failures and understanding the primary elements of these failures.
Safety equipment evaluation: Destructive testing is used in the occupational health and safety industry to confirm the protective capacities of safety equipment under physically demanding conditions. For example, certain personal protective equipment (PPE) requires certification under International Electrotechnical Commission (IEC) and ASTM standards, which use destructive test methods.
Hazard identification and safety assurance: Some projects require destructive testing to ensure that workplace structures and machinery will not fail and pose safety hazards when used within their limits.

Drawbacks of Destructive Testing

Though destructive testing is known for its reliability and accuracy, it also has its downsides. If your company is considering performing destructive tests to evaluate your materials, machines or components, you should first understand the drawbacks of doing so.

Resource Waste

When using destructive testing to discover a material’s performance flaws, you must destroy every item you test — that means you may demolish a machine’s vital components or its entire infrastructure. Because destructive tests deem products unsalvagable after testing, you cannot use them again in the future. While some view these losses as necessary, others see them as unnecessary material waste.

High Expenses

Because destructive tests completely destroy test specimens, they result in significant expenses for the companies conducting them. These businesses lose money from material costs and must forfeit more funds to replace them. These expenses can be particularly severe when testing larger infrastructures that cost upwards of millions of dollars.

Due to its weighty costs, destructive testing is only suitable for companies with plentiful materials that can afford to waste and replace resources.

Time Requirements

Destructive material testing is a time-consuming process compared to other testing methods. Because these types of tests involve manual processes, they’re not as efficient as automated methods. Destructive tests also require extensive prep and prolonged inspection times. Companies must also shut down job site operations to administer testing, leading to increased downtime.

Distance Limitations

When conducting destructive tests, inspectors must interact directly with the test specimens. Due to these hands-on procedures, you cannot use destructive methods to detect machine flaws across long distances as you could with other test types.

What Is Non-Destructive Testing?

Non-destructive testing (NDT) is a set of examination methods that enable inspectors to collect data and evaluate systems, materials or components without causing permanent damage. Like destructive testing, non-destructive tests are also used to pinpoint a test item’s defects.

Types of Non-Destructive Testing

Non-destructive testing is an umbrella term that encompasses many testing methods.

Visual testing: Through visual testing, inspectors gather visual data regarding a material’s status either by looking at the test specimen or using remote visual inspection devices for more in-depth results.
Magnetic particle testing: Non-destructive magnetic particle testing involves identifying material flaws by observing disruptions in magnetic field flow. Through this method, inspectors induce a magnetic field in the asset and position iron particles over its surface to reveal visual defects.
Ultrasonic testing: Inspectors transmit high-frequency waves to a material to evaluate property changes and spot surface imperfections.
Radiography testing: This technique uses X- or gamma-radiation to pinpoint flaws by sending radiation into an asset and observing results on a shadowgraph.
Leak testing: If a vessel leaks, you can use leak testing to determine where the defects lie.
Liquid penetrant testing: Liquid penetrant testing uses a dye to visually reveal any issues and a fluorescent light to further examine them.
Eddy current testing: This electromagnetic testing method is used to measure a material’s magnetic field for the strength of eddy, or electrical, currents to locate defects.

Advantages of Non-Destructive Testing

Non-destructive tests are the ideal methods for testing assets across practically every industry. This technique comes with many advantages that you can’t find with destructive testing.

If you’re debating whether to conduct non-destructive or destructive tests for your company, consider the many benefits of NDT.

Reduced Material Waste

Perhaps the greatest benefit of non-destructive testing is that this process leaves the test sample completely functional while still providing useful insights. That means less wasted resources. Unlike destructive testing, you don’t have to dispose of your materials after testing them. This factor is particularly beneficial for companies testing expensive or limited materials, as they won’t suffer any considerable losses.

Cost Efficiency

Because non-destructive testing preserves test specimens, it results in significant cost savings. With these test methods, you can save money on materials and replacement costs instead of enduring losses through destructive tests.

Using non-destructive testing to identify potential machine problems before malfunctions occur will also save you money by preventing costly equipment repairs and replacements in the future.

Minimal Downtime

Non-destructive processes are highly efficient and take considerably less time to perform than destructive testing. That’s because, with NDT, there’s no need to break down materials for testing purposes or perform repeated manual tests.

You can also test materials while they’re still in use, meaning you won’t have to cease operations during testing, minimizing downtime.

Increased Safety

Non-destructive testing helps companies identify potential issues and determine whether components require improvements or repairs. These tests ensure that machines operate safely, preventing accidents on the job site. When your systems function as they should, you maintain a safe and secure work environment.

Reliable Results

Non-destructive tests detect material defects with high accuracy, producing reliable results. Using these outcomes, you can gain valuable insights regarding product performance and behavior and make adjustments as needed. With more reliable testing and modification comes better product manufacturing.