先进高温合金设备工艺

本发明提供一种船用气阀钢及其制备工艺,包括以下质量百分比的组分:C0.22‑0.28%、Si0.7‑1.3%、Mn0.7‑1.3%、S≤0.02%、P≤0.035%、Cr19.1‑19.8%、Ni9.1‑9.8%、W1.8‑2.5%、Mo0.05%,余量为Fe。本发明以Fe为基体,通过成分设计,控制各元素的质量百分比,Ni、Mo等元素含量均得到削减,实现了成分的减量化,在保证钢材的耐高温腐蚀性能以及强度、硬度等性能的基础上进一步改善钢材的塑性,降低气阀钢的生产成本

表1 钢的牌号及化学成分

Table 1  steel grade and chemical composition

注：钢的成品化学成分允许偏差按GB/T222的有关规定执行。

Note:The permissible tolerances of product analysis shall be as per the rules of GB/T222.

4.2 冶炼方法 Steelmaking method

钢应采用“电弧炉+电渣重熔"的方法冶炼，或非真空感应+电渣。

The steelmaking process shall be EAF+ESR or Non Vacuum Induction

Melting+Electrical Slag Remelting (Non-VIM/IM+ESR) .

4.3 交货状态 Selivery condition

钢棒应以“固溶+削皮+抛光"状态交货，表面粗糙度Ra≦1.6μm。

Steel bars shall be delivered in “solution plus peeling plus polishing",and the suiface roughness Ra shall be no more than 1.0μm.

推荐的固溶处理制度为：980～1050℃保温，快冷。

The solution treatment system is recommended as “solution at 980～1050℃,and rapid cooling".

4.4 低倍组织 Macrostructure

低倍组织按GB/T226检验，钢棒的横截面酸浸低倍片上不得有目视可见的缩了残余、气泡、夹杂和裂纹。按GB/T1979 进行评定，一般疏松、中心疏松及偏析不得超过2.0级。

Cross-section macrostructure test pieces shall be etched and tested as per GB/T226,and they shall be free from visible shrinkage,bubble,crack and inclusion.The acceptable ratings are as follows:General porosilty≦class 2.0,central porosity ≦class 2.0,ingot setregation ≦class 2.0.

4.5 非金属夹杂物 Non-metallic inclusion

钢棒的非金属夹杂物按GB/T10561中的评级图评定，应符合表2的规定。

The non-metallic inclusion of steel bars shall be evaluated in accordance with GB/T10561,and the acceptable level shall conform to requirements of Table 2.

表2 非金属夹杂物要求

4.6 晶粒度 Grain Size

交货状态的钢棒的晶粒度应按GB/T6394检验，晶粒度应不粗于6级。

The grain size of steel bars in the delivery condition shall be tested as per GB/T6394,and the grain size shall be no coarser than No.6.

4.7 机械性能 Mechanical property

交货状态钢棒的机械性能应符合表3的要求。

The mechanical property of steel bars in the delivery condition shall be as per requirements of Table 3.

表3 机械性能要求

Table 3 Mechanical Property at room temperature

4.8 超声波探伤 Ultrasonic testing

钢棒应逐支按照GB/T4162进行超声波探伤。尺寸≦115mm的棒材按*验收：>115-250mm的棒材按B级验收。

Ultrasonic testing shall be performed in accordance with GB/T4162 for each piece of steel bar respectively with Class A acceptable for bars with the dimension of no more than 115mm and Class B acceptable for bars with the dimension ranging from 115mm to 250mm.

4.9 表面质量 Surface quality

钢棒表面不允许有任何裂纹、折叠、划伤等有影响使用的缺陷。

The surface of steel bars shall be free from any crack,loerlap,scratch and other defects that can influence the use of bars.