Fig. 2
Photos and soft X-ray images of the transverse section of sugi heartwood, sugi sapwood and hinoki wood. SH, SS, H in the labels represent sugi heartwood, sugi sapwood and hinoki wood. Labels containing ‘1′ represent the control specimens. Labels containing ‘2′, ‘3′, and ‘4′, respectively, represent the sandwich timbers with surfaces compressed (preheating time: 15 s), interior compressed (preheating time: 180 s) and center compressed (preheating time: 1500 s) when the compression is 6 mm or 5 mm; ‘5′, ‘6′, ‘7′ in the labels represent the sandwich wood with surface compressed, interior compressed and center compressed when the compressing distance is 10 mm; labels containing ‘A’ represent photos; labels containing ‘a’ represent X-ray images; sections in the yellow rectangle are the area where the density was tested