1500
5.4 Peening and ultrasonic impact treatment Peening and ultrasonic impact treatments have been used in welding applications to reduce local residual stress and improve weld mechanical properties .
 manufacturing process: Peening; process characterization: ultrasonic impact treatment; manufacturing process: Peening; process characterization: ultrasonic impact treatments; manufacturing process: welding; concept or principle: local residual stress; engineering feature: weld; concept or principle: mechanical properties
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 manufacturing process: Peening; process characterization: ultrasonic impact treatment; manufacturing process: Peening; process characterization: ultrasonic impact treatments; manufacturing process: welding; concept or principle: local residual stress; engineering feature: weld; concept or principle: mechanical properties