Segmented concrete blades are laser welded, in this case we have make the diamond blades have high strength and also improve its cutting performance. In order to reduce the stress to the steel core and prevent steel core cracking during cutting some hard materials, we have made undercut segments on the segments to protect the steel cores. They are installed on handheld saw, floor saw, walk-behind saw, using for dry or wet cutting concrete, cured concrete, green concrete reinforced concrete cutting. Laser welded concrete blades have good cutting performance, fast cutting speed and long life.