The quality of the stamping quality of the titanium pla […]
The quality of the stamping quality of the titanium plate depends to a large extent on the smelting process of the titanium plate itself, which has sufficient hardenability to ensure the uniform microstructure and mechanical properties of the entire spring section. The forming process of the titanium plate is similar to the pressure processing of other materials. The surface of the wool and the preform should be coated with paint and lubrication if necessary to reduce the friction between the part and the tool and reduce the scratches. , Improve product quality and extend tool life. Especially during thermoforming, the coating not only relieves the serious friction between the part and the mold at high temperature, but also protects the surface of the part, avoiding and reducing oxidation.
In summary, the purpose of using coatings for titanium sheet stamping is: 1. Improve the surface quality of parts; 2. Protect titanium parts from oxidation; 3. Reduce the pressure required for forming; 4. Extend mold life; 5. Control material Flow during deformation. The coating should generally have the following properties: 1. Good anti-corrosion performance, no harmful ingredients, and will not cause pollution to the material; 2. It has a certain degree of adhesion and is easy to coat; 3. It has sufficient strength and is coated during use. The layer is not easy to be damaged; 4. It has good lubricating performance; 5. It is easy to remove; 6. It is harmless to the health of the operator; 7. The cost is low. The coatings for forming can be divided into two categories according to the different conditions of use, namely, coatings for normal temperature forming (cold forming) and coatings for high temperature forming.
The surface strength of titanium sheet stamping parts is an important factor affecting the fatigue strength. Surface heat treatment and surface cold plastic deformation processing are very effective in improving fatigue strength, such as surface quenching, carburizing, carbonitriding, nitriding, shot peening and rolling. Improving the surface strength of the part can reduce the effective tensile stress and local uneven deformation on the surface of the part, and reduce the formation of fatigue cracks. (l) Grinding off the surface decarburization layer produced by heat treatment can significantly increase the fatigue limit; (2) Direct shot peening without removing the surface decarburization layer produced after heat treatment can increase the fatigue limit by shot peening after removing the decarburization. The former is 30%-50%, and the latter is only 3%-6%. In order to reduce the effect of surface decarburization, the hot-rolled spring round titanium surface is stripped. To avoid surface decarburization, the carbon chemical potential gradient between the two should be eliminated or reduced. Heating with protective atmosphere is an effective measure to avoid or reduce surface decarburization. To shorten the heating time and reduce the depth of decarburization, rapid induction heating should be used. Due to the different effects of different alloying elements on the activity and diffusion of carbon, industrial titanium plates with different compositions under the same conditions will exhibit different decarburization behaviors.