Coercivity of Neodymium magnets, could it be demagnetized in an MRI?

  • Context: Graduate 
  • Thread starter Thread starter magnetics
  • Start date Start date
  • Tags Tags
    Magnets Mri Neodymium
Click For Summary
SUMMARY

The discussion centers on the coercivity of N45 Grade Neodymium magnets, which have a remanence (Br) of 1320 mT and a coercive force (Hcj) of 923 kA/m. It is established that placing an N45 magnet inside a 2T MRI could potentially demagnetize it, as the magnetic field strength exceeds the coercive force of the magnet. The relationship between magnetic flux density (B) and magnetic field strength (H) is defined by the equation B=μo H, indicating that the direction of the field is crucial for demagnetization.

PREREQUISITES
  • Understanding of magnetic properties, specifically coercivity and remanence.
  • Familiarity with Neodymium magnet grades, particularly N45.
  • Knowledge of MRI technology and its magnetic field strengths.
  • Basic grasp of electromagnetic equations, including B=μo H.
NEXT STEPS
  • Research the effects of high magnetic fields on different grades of Neodymium magnets.
  • Learn about the demagnetization process in permanent magnets.
  • Investigate the safety protocols for using magnets in MRI environments.
  • Explore the relationship between coercive force and magnetic field strength in various materials.
USEFUL FOR

Engineers, physicists, and medical professionals involved in MRI technology, as well as anyone interested in the properties and applications of Neodymium magnets.

magnetics
Messages
47
Reaction score
0
An N45 Grade Neodymium Rare Earth magnet has a remnance (Br) of 1320 mT and Coercive force (Hcj) of 923 kA/m.

I am a little confused with the units of Coercive Force, how does A/m relate to Gauss/Tesla?

Also, if an N45 magnet was placed inside a 2T MRI, would that be strong enough to demagnetize it or change its magnetic properties?

Thank you.
 
Physics news on Phys.org
Corresponds to ##\mu_r \approx 1140##

Putting strong magnets in an MRI looks like a bad idea, but I don't know how that would influence the magnet.
 
The relationship between B and H in air is B=μo H.
The 2T correspond to a value of H higher that the coercive field of the magnet so it looks like it can be demagnetized by this field, if the field is in the right direction.
 

Similar threads

Graduate Identifying Magnet Grade for FEMM Simulation: Neodymium Cylinder Magnets
  • · Replies 5 ·
Replies
5
Views
2K
Graduate The Hysteresis Loop of Raw Iron: Understanding Coercivity and Magnetization
  • · Replies 8 ·
Replies
8
Views
3K
Graduate How many magnets do I need to generate 1 kW of power using neodymium magnets?
  • · Replies 3 ·
Replies
3
Views
2K
Graduate Thinking about magnetic coercive field
  • · Replies 3 ·
Replies
3
Views
3K
Undergrad Why do different gauss meters measure magnetic field strength differently
  • · Replies 8 ·
Replies
8
Views
7K
Graduate What is the Definition and Function of a Magnetic Field?
  • · Replies 1 ·
Replies
1
Views
2K
Graduate Electric and Magnetic Units: Definition and Summary
  • · Replies 0 ·
Replies
0
Views
2K
Admissions Could I please get critique on my SOP? (Experimental Biophysics)
  • · Replies 8 ·
Replies
8
Views
982