Applications
Flaws

MISTRAS’ in-depth lab testing services detect material flaws and discontinuities introduced in the manufacturing process that can degrade the structural and operational integrity of your components and assets.

Even the smallest flaws in your assets and equipment can contribute to the development of larger defects, risking operational interference and even complete asset failure.

Whether they are caused by environmental influence, faulty production, or use-related stress, flaws in any componentry should be quickly identified and addressed.

Welded Component Flaws

Welding flaws compromise the usefulness and function of the weld, which can lead to more serious defects and damage within your facility. The causes of welding flaws include poor process conditions, operator error, flawed technique, bad weld grooves, and incorrect consumables. In addition, hydrogen embrittlement and residual stresses can cause flaws in welding while it is in use.

Welding flaws create a huge hazard for the structural and operational integrity of your assets. Some prominent welding flaws that MISTRAS detects include:

• Lack of Fusion – Welded materials that aren’t completely fused together and thus don’t maintain a full seal.
• Incomplete Penetration – The weld does not extend through the thickness of the metal.
• Slag Inclusions – Cooled flux particles that become entrapped in weld metal prevent complete penetration of the weld.
• Porosity – Gas is entrapped in the molten weld, causing cavity-like discontinuities to form.
• Undercut – The angle of the weld is at an inverse U shape when the gun is held at an improper angle, which makes a groove in the weld and decreases strength.
• Cracks – Separations between the joined materials.

Some other common types of welding flaws that can affect welds include lamellar tearing, overcut, and gas inclusion.

Raw Materials and Machined Parts Flaws

In the aerospace and oil & gas industries, material flaws can have serious consequences on the safety and fitness for use of components and assets by greatly decreasing material strength.

Even small material flaws can accumulate into larger defects or accelerate further damage when assets undergo the intense stress that accompanies regular operation. Plastics, metals, composites, and a wide variety of other materials can experience an array of flaws, which is extremely detrimental in any context.

Key flaws in this segment include:

• Laminations – Parallel separations inside metal plates which decrease thickness and reduce strength.
• Surface Cracking – Material separations on the surface of a component.
• Corrosion – Oxidation in a metal that breaks down the material by forming small pits in the surface, which degrades the material and reduces quality and strength.

Some other common raw materials and machined parts flaws include:

• Porosity
• Voids
• Cold Shut
• Hot Tears
• Nonmetallic Inclusion
• Shrinkage

Casting Flaws

Casting flaws include any irregularities or discontinuities that occur during the metal casting process. When the casting process is interrupted, flaws can occur in a material, including surface and subsurface defects.

These flaws occur as a result of a variety of casting process discontinuities, including flawed:

• Pattern designs
• Molds
• Melting practices
• Pouring practices
• Core construction
• Gating system
• Temperature and rate

Casting flaws can cause problems for any assets that require componentry of a specific shape and composition, along with decreasing the strength and integrity of the metal.

When these casting process irregularities occur, it can quickly lead to material defects, some of the most common including:

• Shrinkage – Casting metal reduces in size during the casting process, causing small holes or cracks in the material.
• Tears – Thermal stress causes cracking and separations in the material.
• Inclusions – Unwanted material is included in the casted component, surface discontinuities and reduced quality.
• Gas Pockets – The formation of gas bubbles within the material after it has cooled.
• Cracking – Pouring temperature that is too high causes material to fuse to the casting, causing material cracking upon solidification.

MISTRAS Flaw Solutions

MISTRAS has the capabilities to identify a huge range of flaws in newly-fabricated components and materials to ensure operational integrity. We offer advanced lab services to closely inspect materials through:

• Traditional and Advanced Non-Destructive Testing (NDT)
• Non-Destructive Inspection (NDI)
• Destructive Testing (DT)
• Materials Testing and Analysis