80.0k views
1 vote
Explain the nature of defect in casting process and identify the defects through various NDT techniques.

2 Answers

4 votes

Answer:

Cold dies, weak metal temperature, dusty metal, lack of ventilation, and too much lubricant can cause casting defects.

Step-by-step explanation:

Cold dies, weak metal temperature, dusty metal, lack of ventilation, and too much lubricant can cause casting defects. Gas permeability, shrinkage porosity, warm tears, and stream stains are other potential defects. Caused by poor gating, sharp edges or heavy lubricant, flow traces are mark left on the casting surface.

fiver techniques used to identify defects in material are shown below

1) Liquid Penetrant Testing – Liquid penetrant screening is among the simplest approaches used to identify component defects.

2) Electromagnetic Testing – Electromagnetic testing comprises Eddy Current Testing, Rotating Current Field Quantification and Wireless Field Testing. Above mentioned techniques can identify both surface &underground flaws.

3) Magnetic Particle Testing – Magnetic particle screening is commonly used for the ferromagnetic materials to detect ground and near-surface defects.

4) Ultrasonic testing – Ultrasonic testing makes it possible to identify large and extremely small surface defects

5) Thermal Infrared Testing – Infrared thermography testing is used to measures and maps thermal variations on a substance's surface through thermal imaging equipment.

User Mahesh Babariya
by
6.0k points
4 votes

Answer Explanation:

DEFECT IN CASTING : Defects are undisireable its not matter which type of defect we want no defect in any process casting defect are observed in the material manufacturing in metal casting process.

THESE DEFECTS ARE CLASSIFIED INTO DIFFERENT CLASS :

  • MOLD MATERIAL DEFECT: This defect occur when the property of mold material used is not up to the mark
  • POURING METAL DEFECT: This defect occur due to adoption of wrong techniques for pouring
  • SHRINKAGE DEFECT: This defect occur when the metal used is not enough to compensate the shrinkage of liquid metal
  • METALLURGICAL DEFECT : Hot tears and hot spots are two such defects

NDT (NON DISTRUCTIVE TESTING): It is a inspection of material without distroy the material

there are different types of NDT

  • VISUAL INSPECTION
  • HYDROSTATIC PRESSURE TEST
  • MAGNETIC PARTICAL INSPECTION
  • ULTRASONIC INSPECTION
User ADEpt
by
5.5k points