TY - JOUR

T1 - NMR-measurements for determination of local moisture content of coated wood

AU - Johansson, Jimmy

AU - Blom, Åsa

AU - Dvinskikh, Sergey

PY - 2013/9

Y1 - 2013/9

N2 - Local increased moisture content (MC) in wood constructions may result in different kinds of mechanical and, especially, biological degrading problems. Therefore, it is of great importance to control the MC of the material. However, there is at present no appropriate method for determining local MC in wood without destroying the product itself. Nondestructive measurements of local MC in wood is significant for the possibility of, for instance, monitoring the in situ MC in wood constructions over time, and thereby predicting potential problems. The nuclear magnetic resonance (NMR) technique has been shown to be valuable for the measurement of MC in wood. In this study, the possibility of utilizing this technique for local MC measurement in wood has been tested on wood samples exposed to water absorption for 72 h. The samples came from three different wood species treated with paint systems available on the market. In the wood samples an artificial "crack" had been created in the paint to introduce an area where the water could easily gain access to the wood. The results show the possibility of using the NMR technique for local MC measurements in wood. The measurement area, however, must be related to the properties of the material. In the case of wood, the measurement spot must be related to the early/latewood proportions. Further, a calibration of the NMR measurement must be made in relation to the expected density variations of the material.

AB - Local increased moisture content (MC) in wood constructions may result in different kinds of mechanical and, especially, biological degrading problems. Therefore, it is of great importance to control the MC of the material. However, there is at present no appropriate method for determining local MC in wood without destroying the product itself. Nondestructive measurements of local MC in wood is significant for the possibility of, for instance, monitoring the in situ MC in wood constructions over time, and thereby predicting potential problems. The nuclear magnetic resonance (NMR) technique has been shown to be valuable for the measurement of MC in wood. In this study, the possibility of utilizing this technique for local MC measurement in wood has been tested on wood samples exposed to water absorption for 72 h. The samples came from three different wood species treated with paint systems available on the market. In the wood samples an artificial "crack" had been created in the paint to introduce an area where the water could easily gain access to the wood. The results show the possibility of using the NMR technique for local MC measurements in wood. The measurement area, however, must be related to the properties of the material. In the case of wood, the measurement spot must be related to the early/latewood proportions. Further, a calibration of the NMR measurement must be made in relation to the expected density variations of the material.

KW - Magnetic resonance imaging

KW - MRI

KW - Nondestructive moisture measurements

KW - Nuclear magnetic resonance

KW - Portable NMR

KW - Risk analysis

KW - Wood coating

UR - http://www.scopus.com/inward/record.url?scp=84884284429&partnerID=8YFLogxK

U2 - 10.1007/s11998-013-9484-4

DO - 10.1007/s11998-013-9484-4

M3 - Article

AN - SCOPUS:84884284429

VL - 10

SP - 601

EP - 607

JO - Journal of Coatings Technology and Research

JF - Journal of Coatings Technology and Research

SN - 1945-9645

IS - 5

ER -