Sinter-Bonding of AISI 316L and 17-4 PH Stainless Steels

Abstract

The sinter-bonding method was used to produce AISI 316L/17-4 PH components by conventional powder metallurgy technology. The production process consisted of following steps: the powder layering, copressing and co-sintering processes. The co-sintering process was carried out at different sintering temperatures (1200, 1250 and 1300°C), and times (60, 90 and 120 min) in hydrogen atmosphere. The effect of co-pressing and co-sintering conditions on the ability to create a permanent connection between AISI 316L and 17-4 PH stainless steels was investigated. The densification, dimensional change and microstructural evolution of sintered AISI 316L/17-4 PH components were studied. The increase in co-pressing pressure as well as using of the longer time and the higher temperature of co-sintering process contributed to increase in AISI 316L/17-4 PH component density. The dilatometric study as well as dimensional changes measurements revealed an appropriate sintering compatibility for AISI 316L and 17-4PH steels when the sintering process was carried out at the temperature of 1200°C for time ranging from 60 to 120 min and at 1250°C for shorter sintering times. The sintering at temperature of 1300°C (regardless of other manufacturing conditions) led to a significant deviation from the cylindrical shape of samples, as a result of difference of shrinkage of AISI 316L and 17-4 PH steels. Microstructural study indicated that AISI 316L and 17-4 PH steels creates a good diffusion joint (without any cracks and warpage) during the hightemperature sintering process. Nickel diffusion takes place from the AISI 316L to 17-4 PH stainless steel, and copper and molybdenum diffuse in opposite direction of nickel diffusion. It is possible to achieve a solid connection between two materials exhibiting difference in chemical composition by using sinter-bonding and conventional powder metallurgy technology.

A review on the production of 17-4PH parts using press and sinter technology

“…The effect of cold pressing and particle size on green densities of 17-4PH pressed parts according to (a) earlier studies (constructed from Refs. 3,11,20,27 ) and by (b) the practical work in this study. distribution has been investigated, which is also presented in Figure 4(a).…”

“…Earlier attempts for proving densification of 17-4PH parts by the press and sinter compared to the injected and sintered parts (constructed from Refs. 3,9,7,11,14,20,26,27,28,29,30,31,32 ). achieve a relative sinter density of 93.47%.…”

“…The densification is considerably affected by many forming factors such as cold pressing, powder compressibility, powder particle shape, particle size distribution, lubricant addition, sintering temperature and time, and sintering atmosphere. Therefore, this review article focuses on the 17-4PH materials produced by PSM and compares them with those produced by MIM, summarizes the latest research on the forming factors, investigates the causes of low densification results, and finds the 3,11,20,27,33 ). theoretical solutions to approve the densification property.…”

“… The densification results from previous press and sinter 17-4PH parts as a function of cold pressing and sintering temperature (obtained by Refs. 3 , 11 , 20 , 27 , 33 ). …”

Prediction of Air Leakage Rate of Sintering Furnace Based on BP Neural Network Optimized by PSO

“…Therefore, sinter has always been the main raw material for blast furnace ironmaking. It mainly determines the technical and economic indicators of blast furnace smelting production [9][10][11][12][13]. In blast furnace ironmaking, the use ratio of sinter basically accounts for about 75% of the blast furnace burden and more than 70% of the blast furnace ironmaking cost and energy consumption.…”