【单选题】
碳当量___时,钢的淬硬冷裂倾向不大,焊接性优良。
A. 小于0.40%
B. 小于0.50%
C. 小于0.60%
D. 小于0.80%
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答案
A
解析
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相关试题
【单选题】
国际焊接学会的碳当量计算公式只考虑了___对焊接性的影响,而没有考虑其他因素对焊接件的影响.
A. 焊缝扩散氢含量
B. 焊接方法
C. 构件类型
D. 化学成分
【单选题】
低合金结构钢焊接时的主要问题是___。
A. 应力腐蚀和接头软化
B. 冷裂纹和接头软化
C. 应力腐蚀和粗晶区脆化
D. 冷裂纹和粗晶区脆化
【单选题】
屈服点在___Mpa以上的低合金结构钢焊接时,一般需要顶热
A. 275
B. 295
C. 345
D. 390
【单选题】
___不是厚板窄间隙焊的优点。
A. 生产率高
B. 不易产生夹渣
C. 热输入量小
D. 焊接材料和能源消耗低
【单选题】
我国窄间隙埋弧焊焊接钢板最大厚度可达___mm。
A. 250
B. 300
C. 350
D. 400
【单选题】
16Mn钢焊接时,焊条应选用___。
A. E4303
B. E4315
C. E5515—G
D. E5015
【单选题】
15MnV钢属于___钢。
A. Q345
B. Q390
C. Q420
D. Q490
【单选题】
在高温、高压蒸汽的运行条件下碳钢的最高工作温度为___℃
A. 350
B. 450
C. 550
D. 650
【单选题】
珠光体耐热钢的焊接性主要是易产生___。
A. 冷裂纹和晶间腐蚀
B. 冷裂纹和应力腐蚀
C. 热裂纹和晶间腐蚀
D. 冷裂纹和再热裂纹
【单选题】
珠光体耐热钢焊条电弧焊焊后应立即进行___。
A. 中温回火
B. 高温回火
C. 退火
D. 低温回火
【单选题】
牌号为W707的焊条是___焊条。
A. 结构钢
B. 珠光体耐热钢
C. 低温钢
D. 奥氏体不锈钢
【单选题】
不锈钢中铬的质量分数均大于___。
A. 25%
B. 23%
C. 18%
D. 12%
【单选题】
奥氏体不锈钢焊接时,如果焊接材料选用不当或焊接上艺不合理时,会产生___等问题
A. 接头软化和热裂纹
B. 降低接头抗晶间腐蚀能力和冷裂纹
C. 降低接头抗晶间腐蚀能力和再热裂纹
D. 降低接头抗晶间腐蚀能力和热裂纹
【单选题】
牌号为A137 的焊条是___
A. 奥氏体不锈钢焊条
B. 低合金钢焊条
C. 珠光体耐热钢焊条
D. 碳钢焊条
【单选题】
___不是焊缝内部缺陷。
A. 未熔合
B. 未焊透
C. 焊瘤
D. 夹渣
【单选题】
___不是促成冷裂纹的主要因素。
A. 钢种淬硬倾向大,产生淬硬组织
B. 接头受到的拘束应力大
C. 较多扩散氢的存在和聚集
D. 较多氧的存在和聚集
【单选题】
___不是防止未熔合的措施。
A. 焊条角度和运条要合适
B. 认真清理坡口和焊缝上的脏物
C. 稍大的焊接电流,焊接速度不够快
D. 按规定参数严格烘干焊条、焊剂
【单选题】
下列缺陷一般除___外,均需进行返修。
A. 深度不大于0.5mm、连续长度不大于100mm的咬边
B. 焊缝表面有气孔、夹渣
C. 焊缝内部有超过图样和标准规定的缺陷
D. 焊缝表面有裂纹
【单选题】
弯曲试验的目的是测定焊接接头的___。
A. 强度
B. 塑性
C. 韧性
D. 硬度
【单选题】
在射线探伤胶片上多呈略带曲折的、波浪状的黑色细条纹,有时也呈直线状,轮廓较分明,两端较尖细,中部稍宽,不大有分枝,两端黑度较浅的缺陷是___。
A. 气孔
B. 夹渣
C. 未焊透
D. 裂纹
【判断题】
在910~1300 ℃的面心立方晶格的铁称γ-Fe
A. 对
B. 错
【判断题】
渗碳体是铁和碳的化合物,分子式为Fe3C其性能软且韧
A. 对
B. 错
【判断题】
将钢加热到A1以下一般为750~800 ℃,保温一段时间后缓慢冷却(一般随炉冷)以消除残余应力的热处理工艺,称为消除应力退火
A. 对
B. 错
【判断题】
合金钢中,合金元素的质量分数的总和大于5%的钢称为高合金钢
A. 对
B. 错
【判断题】
根据GB/T221—2000规定,合金结构钢牌号头部用两位阿拉伯数字表示碳的质量分数的平均值(以千分之几计)
A. 对
B. 错
【判断题】
原子核由带正电荷的质子和不带电的中子组成
A. 对
B. 错
【判断题】
焊接烟尘的来源是由熔化金属及熔渣在过热条件下产生的高温蒸气经氧化,冷凝而形成的
A. 对
B. 错
【判断题】
管件对接的定位焊缝长度一般为25~30mm,厚度一般为4~5mm.
A. 对
B. 错
【判断题】
焊条电弧焊立焊操作时,发现椭圆形熔池下部边缘由比较平直轮廓变成鼓肚变圆时,表示熔池温度已稍高或过高,应立即灭弧,降低熔池温度,以避免产生咬边
A. 对
B. 错
【判断题】
CO2焊用于焊接低碳钢和低合金高强度钢时,主要采用通过焊丝的锰钛联合脱氧的方法
A. 对
B. 错
【判断题】
CO2焊时,当焊接电流逐渐增大时,熔深、熔宽和余高都相应地增加
A. 对
B. 错
【判断题】
对焊机按工艺方法分有通用对焊机和专用对焊机
A. 对
B. 错
【判断题】
不等厚度材料点焊时,为防止熔核偏移造成焊点强度大大下降,一般规定工件厚度比不应超过1:5
A. 对
B. 错
【判断题】
冷轧低碳钢焊接热影响区由过热区、正火区和部分相变区三部分组成
A. 对
B. 错
【判断题】
珠光体耐热钢焊条是根据母材的高温强度来选择的
A. 对
B. 错
【判断题】
加热温度950~1250℃是不锈钢晶间腐蚀的危险温度区,或称敏化温度区
A. 对
B. 错
【判断题】
为了防止奥氏体不锈钢焊接热裂纹,希望焊缝金属组织是奥氏体-铁素体双相组织,其中铁素体的质量分数应控制在15%左右
A. 对
B. 错
【判断题】
钨极直径太小、焊接电流太大是产生未焊透的原因之一
A. 对
B. 错
【判断题】
磁粉探伤适用于检测非导磁性材料的表面和近表面的缺陷
A. 对
B. 错
【判断题】
我国射线 探伤标准规定,焊缝质量分为四个等级,I级焊缝内允许有少量的气孔和夹渣
A. 对
B. 错
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【单选题】
An administrator is attempting to power on a virtual machine with 32GB of memory. The operation fails with the following error: <Could not power on VM: No space left on device> <Checking the space on the virtual machine's datastore, there is 30GB free.> Which action would allow the VM to power on?___
A. Set a 2GB memory reservation on the VM.
B. Mount the virtual disk from the affected VM on to another virtual machine and free up space from within the OS.
C. Enable vSphere HD admission control on the cluster in which the VM resides.
D. Set a 2GB memory limit on the VM.
【单选题】
An administrator attempts to manually reclaim space on thin-provisioned VMFS6 volumes but finds that no additional space is being recovered. Which could be causing this?___
A. vSphere 6.5 does not support manual UNMAP.
B. The manual UNMAP operation has been moved to the vSphere web client.
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【单选题】
An administrator has upgraded to vSphere 6.5 and also wants to use Kerberos authentication for NFS. Which can be done to the existing NFSv3 volumes to enable this feature?___
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C. Nothing. All NFSv3 mounted datastores are upgraded automatically during vSphere upgrades.
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【单选题】
An administrator wants to restore the vCenter Server Appliance 6.5 from backup. Where can this be accomplished?___
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D. from the vCenter Server Appliance Installer
【单选题】
The administrator wants to power on VM-K2, which has a 2GHz CPU reservation. VM-M1, VM-M2, and VM-K1 are all powered on. VM-K2 is not powered on. The exhibit shows the parent and child resource reservations. If Resource Pool RP-KID is configured with an expandable reservation, which statement is true?___
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B. VM-K2 will be able to power on since resource pool RP-KID has 2GHz available.
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D. VM-K2 will receive resource priority and will be able to power on this scenario.
【单选题】
Which is the block size on the VMFS6 datastore?___
A. All small and large file blocks are 8MB.
B. All small and large file blocks are 1MB.
C. Small file blocks are 512KB. large file blocks are 64MB.
D. Small file blocks are 1MB, large file blocks are 512MB.
【单选题】
When installing vCenter Converter Standalone, why must an administrator perform a client-server installation instead of a local installation?___
A. to manage conversion tasks remotely
B. to convert virtual machines as well as physical machines
C. to allow installation of the Converter agent on remote source machines
D. to hot clone physical or virtual machines
【单选题】
Which is required by vCenter Converter Standalone to convert a physical Red Hat Enterprise Linux 7 machine to a virtual machine?___
A. The Linux machine must be powered off.
B. The Linux machine must have the SSH daemon started.
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【单选题】
An administrator is troubleshooting network communications between a vCenter Server and an ESXi 6.5 host. Which log shows the related events between these components?___
A. /var/log/fdm.log
B. /var/log/vpxa.log
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D. /var/log/auth.log
【单选题】
An administrator has recently upgraded from vSphere 6.0 to 6.5, and can no longer see the software iSCSI named vmhba33. Which could be the reason for this?___
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C. vSphere 6.5 no longer supports software iSCSI.
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【单选题】
An administrator is trying to vMotion a VM from his datacenter to a recovery site. Which is the maximum allowed RTT (Round-Trip Time) latency between source and destination host?___
A. 100 milliseconds
B. 150 milliseconds
C. 15 milliseconds
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【单选题】
Which is required for configuring iSCSI Software Adapter network port binding?___
A. VMkernel of the iSCSI traffic must be load balanced using Route based on IP Hash algorithm.
B. VMkernel of the iSCSI traffic must be load balanced using Route based on Source Virtual Port ID algorithm.
C. VMkernel of the iSCSI traffic must be load balanced using Route based on Source MAC Hash algorithm.
D. VMkernel of the iSCSI traffic must be bound to only one active network adapter.
【单选题】
In vSphere Data Protection 6.1, which is the function of a Backup Verification job?___
A. None. Backup Verification job is not a feature of vSphere Data Protection
B. It is a manual task -Power it on -Verify the guest OS -Check started applications
C. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OS is booted by communicating with the Backup Verification agent
D. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OC is booted by detecting the VMware ToolsTM "heartbeats"
【单选题】
An administrator has enabled vSphere Distributed Switch Health Check. The hosts connected to that Distributed Switch all display an alert:< vSphere Distributed Switch MTU supported status > .The administrator has all of the VMkernel ports MTU sizes set to 1600. Which action will remedy this problem?___
A. Configure the Distributed Switch to MTU 9100.
B. Disconnect and reconnect the physical network cable.
C. Configure the physical switch to MTU 1600.
D. Disable the Distributed Switch MTU.
【单选题】
Which Host Profile Subprofile configuration is used to configure firewall settings for ESXi hosts?___
A. Advanced Configuration Settings
B. General System Settings
C. Security
D. Networking
【单选题】
Where would a vSphere administrator find general vCenter Server logs on a vCenter Server Appliance?___
A. /var/log/vmware/vpxd/
B. /var/log/messages
C. /etc/vmware-vpx/
D. /var/log/vmware/vsan-health/
【单选题】
An administrator wishes to enable network port mirroring based on source port. Which feature should be enabled?___
A. vSphere standard switch port
B. ERSPAN
C. NSX Virtual Wire
D. VLAN
【单选题】
Which CLI command shows the physical uplink status for a vmnic?___
A. esxcli network ip connection list
B. esxcli network ip neighbor list
C. esxcli network nic get
D. esxcli network nic list
【单选题】
Which is the maximum number of block devices (LUNs) that are supported by ESXi hosts that are running version 6.5?___
A. 1024
B. 512
C. 2048
D. 256
【单选题】
When performing a vCenter Server 5.5 for Windows with Microsoft SQL Server Express database migration to vCenter Server Appliance 6.5, which will be the target database?___
A. Microsoft SQL Server Express 2012R2
B. Microsoft SQL Server Standard 2012R2
C. PostgreSQL
D. Oracle DB 11g
【单选题】
An administrator has multiple vCenter Server 6.5 systems but cannot enable Storage I/O Control (SIOC) on a datastore shared by ESXi hosts managed by the vCenter Server systems. Which action should the administrator take to resolve the issue?___
A. Unmount the datastore and then enable SIOC on the vCenter Server system.
B. Configure the datastore to be managed by a single vCenter Server system.
C. Configure Storage DRS and then enable SIOC on the vCenter Server system.
D. Enable Raw Device Mapping (RDM) on the
E. SXi hosts.
【单选题】
“OneAppServer” is a VM template stored in a content library named “LibraryOne”, but the vSphere administrator is not able to use this template for deployment. Why is the administrator unable to deploy OneAppServer?___
A. OneAppServer must be updated before it can be deployed.
B. LibraryOne is a subscribed library and OneAppServer is not downloaded yet.
C. LibraryOne is published and optimized for syncing over HTTP.
D. OneAppServer was imported from a local file on the system.
【单选题】
An administrator sets the Failover Capacity for both CPU and Memory at 25%. Based on the Exhibit below, how much of the cluster’s total CPU resources are still available to power on additional virtual machines?___
A. 45%
B. 25%
C. 70%
D. 60%
【单选题】
Which statement applies to the vSphere Replication appliance?___
A. Only one vSphere Replication appliance can be deployed per vCenter Server instance.
B. VMware Tools in the vSphere Replication appliance can be upgraded.
C. A single vSphere Replication appliance can manage a maximum of 4000 replications.
D. vSphere Replication is available only with the vSphere
E. ssentials Plus license.
【单选题】
Which esxcli namespace can a vSphere Administrator use to adjust the queue depth?___
A. esxcli system module parameters
B. esxcli storage core device
C. esxcli system module set
D. esxcli storage core adapter
【单选题】
Which statement regarding datastore clusters meets VMware’s recommended best practices?___
A. Clusters should contain only datastores presented from the same storage array.
B. Clusters should contain only datastores with equal hardware acceleration capability.
C. Clusters should contain only datastores with the same capacity.
D. Clusters should contain only datastores using the same connection method (iSCSI, FC, etc.).
【单选题】
What VM Monitoring setting would ensure that the maximum reset window for a virtual machine is 24 hours?___
A. Medium
B. Low
C. High
D. Normal
【单选题】
What is the default space threshold for vSphere Storage DRS?___
A. 80%
B. 70%
C. 90%
D. 95%
【单选题】
Which is the correct sequence to upgrade a vSphere infrastructure?___
A. vCenter Server>ESXi host> VMware Tools>VM compatibility
B. ESXi host>vCenter Server> VMware Tools>VM compatibility
C. vCenter host> ESXi host> VM compatibility> VMware Tools
D. ESXi host>vCenter Server> VM compatibility>VMware Tools
【单选题】
An administrator has a large boot from SAN cluster and wants to ensure consistent configuration by using host profiles. What special considerations are required for boot from SAN hosts?___
A. Change the “Device is shared clusterwide” setting to “false” in the host profile.
B. Verify that the boot LUN is correctly identified as the boot device in the host profile.
C. The boot from SAN device must report as a local device.
D. Host profiles are incompatible with boot from SAN hosts.
【单选题】
When using VMware Converter to import a Windows server and improve the consistency of the destination virtual machine, which optional step can be performed immediately prior to powering down the source server?___
A. Perform a final synchronization task.
B. Remove the server from the network.
C. Uninstall production applications.
D. Remove the server from the Active Directory domain.
【单选题】
Restoration of the vCenter Server Appliance is accomplished using which interface?___
A. vSphere Web Client
B. vSphere Client
C. vCenter Server Appliance Management Interface
D. vCenter Server Appliance GUI Installer
【单选题】
When attempting to migrate a virtual machine to another host in the same cluster, the error message, “Select a valid compute resource” returns. What could cause this error?___
A. Both hosts run different versions of ESXi.
B. Both hosts are not sharing the same datastore.
C. VMware Tools is not installed.
D. Virtual machine has an ISO attached.
【单选题】
When will vSphere Data Protection delete the expired backup image of a Platform Service Controller?___
A. Immediately after the retention period has expired.
B. After the expired backup image is restored.
C. During the next backup window following expiry.
D. During the next maintenance window following expiry.
【单选题】
Group A has permission to download files in Content Library. Group B does not have permission to download files in Content Library. If a user is a member of both groups, what will be the result?___
A. The user cannot download file from Content Library.
B. The user can download file from Content Library.
C. The user cannot access Content Library.
D. The user can access Content Library.
【单选题】
An administrator is trying to set up Host Partial Failure Response, but the Automated option is grayed out. What can the administrator change to enable the Automated option?___
A. Change the vSphere DRS Automation level to Partially Automated.
B. Change the vSphere DRS Automation level to Fully Automated.
C. Enable vSphere HA Host Monitoring.
D. Change the vSphere DPM Automation level to Automatic.
【单选题】
When you attempt to open a virtual machine console from the vSphere Web Client, the console does not connect. The following error message appears:<HTTP ERROR 404> <Problem accessin/.Reason: Not Found>. Why did not connect?___
A. Port 443 is in use.
B. Port 9443 is in use.
C. Port 8443 is in use.
D. Port 22443 is in use.
【单选题】
What new feature was introduced to the Content Library in vSphere 6.5?___
A. Mount an ISO directly from the Content Library.
B. Deploy a virtual machine from an OVF Package in a Content Library.
C. Upload a File from a URL to a Library Item.
D. Upload a File from a Local System to a Library Item.
【单选题】
How can an administrator exclude Encryption rights from a support engineer?___
A. Clone the role Virtual machine power user, remove Cryptographic operations privileges.
B. Clone the role Administrator and assign to the support engineer.
C. Clone the role Virtual machine power user and assign to the support engineer.
D. Clone the role No cryptography administrator and select privileges only for the support engineer.
【单选题】
The administrator must back up a vCenter HA deployment. Which component must be backed up?___
A. Passive node
B. Witness node
C. External database
D. Active node