Do you Know the Choice of Bucket Tooth Welding Materials?

As a Volvo Style Pin Wholesale, share with you.

In order to improve the wear resistance of Volvo Bucket Teeth surface, it is very necessary to choose a reasonable welding material during surfacing. The selection principle of high-manganese steel substrate surface surfacing welding materials is that as long as it can withstand material impact and can withstand large impact loads during use, it is necessary to choose hardfacing with high hardness and good wear resistance. 

Volvo Bucket Teeth

The base material of the bucket teeth is mostly austenitic high-manganese steel, so the type of EDMn-B-16 high-manganese steel surfacing electrode is used during welding repair. The filler metal of this electrode is austenitic high-manganese steel, and molybdenum is added to the filler metal to improve the crack resistance and abrasion resistance of the weld metal. Therefore, the electrode after surfacing of the electrode is used. The surface has the characteristics of work hardening, high toughness and good wear resistance. The surface hardness of the surfacing metal can reach HB≥170.

Because ZGMn13 belongs to high-carbon steel, its weldability is relatively poor: on the one hand, it is easy to precipitate carbides in the heat-affected zone of the welding and cause embrittlement of the material; on the other hand, the tendency of hot cracks in the weld is more serious, especially near the weld Easy to produce liquefaction cracks. Therefore, before welding, a reasonable welding process must be formulated to ensure the quality of the surfacing metal layer and reduce the occurrence of welding defects.

Bucket tooth welding process measures

I. Welding process measures

Because ZGMn13 austenitic high-manganese steel has poor weldability, a welding method with concentrated heat source and low welding line energy should be used in welding. The process is as follows:

(1) Before welding, the impurities such as dirt, oil and rust must be cleaned and polished until the metal luster is exposed. Carefully inspect the place to be welded for defects such as delamination, cracks, sand inclusions and pores. If these defects are found, they must be removed with a grinder or arc gouging to ensure the quality of the weld during surfacing.

(2) Use a 3.2mm diameter electrode with low current (100 ～ 120A) for welding. Dry the electrode in accordance with the instructions before use. When welding, do not swing the electrode as much as possible. If you need to swing, do not swing more than 3 times the diameter of the electrode. Use a narrow bead as much as possible.

(3) Pre-heating should not be performed before welding, and the inter-layer temperature should not exceed 300 ° C during multi-layer welding. Use small line energy as much as possible during welding to minimize the heating time of the basic metal. The power source should be reversed. Intermittent welding, water cooling to normal temperature immediately after welding. Accelerate the cooling rate of welded joints and minimize the residence time after welding to the temperature range of 950 ～ 250 ℃. A large amount of carbides will precipitate in this temperature range, which will cause the base material to become brittle.

(4) A hammer can be used to strike the weld metal area before water cooling after welding to eliminate the stress generated during welding.

Our company also has Volvo Style Pin on sale, welcome to consult.