Versatile Magnetic Testing for Rough and Hot Surfaces
Dry Powder Magnetic Particle Testing (DPMPT) is a practical variation of the Magnetic Particle Testing (MT) technique designed for detecting surface and near-surface flaws in ferromagnetic materials. Instead of a liquid suspension, this method uses fine, dry magnetic particles in various contrasting colors such as red, yellow, or black.
The component is magnetized, and the powder is gently dusted or blown across its surface. If discontinuities exist, magnetic flux leakage attracts the particles to the flaw edges, forming clear visible indications under white light. It is particularly suitable for inspecting rough, porous, or high-temperature surfaces where liquid-based methods are impractical.
BQCIS applies DPMPT in field conditions, workshop environments, and high-heat applications such as welds, castings, and large structural fabrications, following ASTM E1444/E709.
Key Dry Powder MT Activities
Key Benefits of Dry Powder MT
Ideal for Rough Surfaces
Performs effectively on castings, welds, and textured materials where wet suspension methods lose clarity.
High-Temperature Capability
Can be applied on components operating up to 400°F (204°C) without evaporative issues common in wet techniques.
Portable & Flexible
Minimal setup and equipment required — ideal for on-site inspections and large or immobile structures.
Cost-Effective Solution
Low-cost consumables and simple operation make it an economical choice for repetitive field testing.
Success Story
Dry Powder MT Reveals Cracks in Heavy Steel Casting
A large heat-treated steel casting for heavy machinery required inspection for surface cracks prior to machining, but its rough surface made liquid penetrants unsuitable.
BQCIS NDT specialists applied the Dry Powder MT method using a high-contrast powder and AC yoke magnetization in the field.
The dry powder clearly highlighted linear crack indications across multiple regions, enabling early defect repair and saving significant post-machining costs.