Inconel 600 Evaporator

The new alloy 13
According to the study of nickel and chromium on stress corrosion resistance of Ni - Fe - Cr alloy of a large number of experimental results, the influence of the domestic development in the 1970 s a kind of high temperature water containing Cl - and [O] stress corrosion resistance is superior to the 18 8 stainless steel and 00 cr20ni32fe (Incoloy 800), 0 cr15ni75fe (Inconel 600) of new alloy (13), the alloy in high temperature water containing 1% and 10% NaOH also has good performance, it is a kind of suitable for PWR evaporator of new materials, applies to Cr18 - Ni8 austenitic stainless steel is easy to produce stress corrosion of all kinds of heat exchangers in chemical, petrochemical and other environment, etc.

General corrosion
In PWR high temperature water medium, alloy and stainless steel corrosion resistance is also an important technical index, general corrosion resistance has a direct influence on is one or two loop system working medium pollution degree of critical data.New alloys in high temperature water 13 comprehensive corrosion performance data in the following table, the data showed that its comprehensive corrosion resistance close to 18-8, 00 cr20ni32alti, 0 cr15ni75fe, evaporator PWR is completely can meet the material requirements for general corrosion resistance.

Pitting
At 35 ℃ and 5% NaCl + 0.005 mol/L - H2SO4 aqueous solution of new alloy of 13 pitting breakdown potential time as a result, compared with other alloy under the same conditions test, new 13 pitting corrosion resistance is superior to the 18 8 stainless steel, is superior to 00 cr20ni32alti (I - 800), and 0 cr15ni75fe alloy (I - 600).In 40 ℃, 10% FeCl3 + 0.05 mol/L HCl test also confirmed the test results.In the pH = 7 boron high temperature water, through 4000 ~ 5000 h test is not a new alloy 13 pitting.

Intergranular corrosion
C 0.03% or less, in the strict control of alloy Ti/C 8 or more, and have a small group the results under the premise of new alloy 13 can test by using the method of GB 1223-84;In boron is 700 ~ 800 parts per million, H2 is 10 ~ 80 g/kg water, Li was 1.6 ~ 2.4 mg/L, pH = 7, temperature of 335 ℃ water loop, as well as pH = 7, 300 ℃, high purity water sensitizing alloy tube and pipe welding joint intergranular corrosion was not found.However, because of low alloy carbon content in the process of pipe production, when using improper lubrication and degreasing process, the alloy hui to overheating processing and carburizing, when pickling, the carburized layer produces intercrystalline corrosion, should take note.

Stress corrosion
1. The high temperature water 13 new alloys in high temperature water containing Cl - and [O] (290 ~ 316 ℃) has good endurance corrosion performance, double U sample after 10000 h static autoclave test results did not produce stress corrosion cracking.Under the same test conditions, 18 8 stainless steel in a short period of time to produce crystal breakdown stress corrosion fracture, stress corrosion cracking resistance of the optimal type of ultra-low carbon Incloy800 (00 cr20ni32alti) and Inconel600 (0 cr15ni75fe) alloy is intergranular stress corrosion cracking, the rupture life vary with test conditions, the former's longest break time of 10000 h, the latter is only 5000 h.Only in test of alloy Inconel690 cr30ni60fe10 (0) and the new 13 alloy without fracture.
2. The high temperature water containing NaOH in two contains NaOH high temperature water, the stress corrosion properties of the new 13 with Inconel690 cr30ni60fe10 (0).With new alloy 13, 18 8 stainless steel, ultra-low carbon Incoloy (00 cr20ni32alti) and Inconel 600 materials such as pipe manufacturing evaporator simulation, after long-term operation shows that the new 13 alloy corrosion resistance, pitting corrosion, stress corrosion, etc.) is far better than 18 8 stainless steel, also is better than that of low carbon Incoloy800 and Inconel600 alloy, especially does not work under the stress of the 18-8 supporting tube of stainless steel corrosion (SCC, PC, etc.), the damage is very serious.

Mechanical properties
New alloy at room and high temperature mechanical properties of 13 in the following table, the data in the table shows that the alloy's mechanical properties close to ultra-low carbon Incoloy800 alloy, and reduce with the increase of solid solution treatment temperature.

Hot working and formability
New alloy 13 thermoplastic slightly lower than 1 cr18ni9ti stainless steel, but still has a good thermal deformation performance, easy to hot working.Laboratory test and production practice show that the alloy suitable period, rolling hot working temperature is 1000 ~ 1150 ℃.New alloy 13 easy cold, the cold work hardening tend to be lower than 1 cr18ni9ti.In setting up the manufacturing process of cold and hot forming performance similar to general austenitic stainless steel, the heat pipe evaporator U type of the small and medium-sized R is subject to eliminate stress treatment.

Welding performance
The alloy weldability below 18 8 stainless steel, but he was elected with filler metal alloy welding process can obtain satisfactory results.Crack resistance of the alloy with 00 cr20ni32alti and 0 cr15ni75fe fairly.In order to obtain good weldability and ensure good stress corrosion resistance of alloy, alloy of impurity phosphorus amount should be kept under strict control.General method of this alloy can be welded stainless steel welding, no special difficulties.

Heat treatment process
The alloy heat treatment process is simple, the solid solution treatment, quick cold can, but U transfer in the evaporator heat pipe bending radius is also the need for eliminating stress.

The application
New 13 alloy corrosion resistant, mechanical properties, such as heat treatment process is simple, cold, hot working, such as welding process performance is good, can produce plates, tubes, wire, tape, forgings and other metallurgical products.This alloy is mainly used for pressurized water reactor nuclear power plant steam generator of the pipe, also can be used in chemical, petrochemical and other industrial stress corrosion resistance of various kinds of heat exchanger, heat exchange equipment